A comparison of the cholinesterases of an oyster (Crassostrea virginica) and a clam (Macrocallista nimbosa). Cholinesterase activities in the hearts and ganglia of an oyster (Crassostrea virginica) and a venerid clam (Macrocallista nimbosa) were measured and compared. Tissue extracts were partially purified by ammonium sulfate fractionation followed by gel column chromatography. Enzymatic activity was assayed spectrophotometrically; substrates were acetyl-, butyryl-, and propionylthiocholine (ATC, BTC, PTC). Kinetic constants characterizing each enzyme were derived. At all substrate concentrations, the hydrolysis rates of both clam enzymes were in the order: BTC greater than PTC greater than ATC. With oyster enzymes the ranking was ATC greater than or equal to PTC greater BTC. The specific activities of oyster heart and ganglion enzymes were similar. In contrast, clam ganglion extracts were 75-100 times more active than clam heart extracts and, with any substrate, had greater activity than either oyster enzyme. All enzyme preparations proved to be homogeneous on the bases of constant substrate activity ratios in successive column fractions, and of intermediate velocities with mixed substrates. Six cholinesterase inhibitors were tested. The specific acetylcholinesterase antagonist, B.W. 62C47, WAS MUCH MORE EFFECTIVE AGAINST OYSTER ENZYMES, WHILE THE SPECIFIC ANTIBUTYRYLCHOLINESTERASE, ISO-OMPA, almost totally inhibited calm enzyme activity, but had little effect on oyster. Eserine was the most effective inhibitor of both enzymes. In conclusion, the enzymes in oyster tissues are acetylcholinesterases, while clam enzymes are butyrylcholinesterases. Nevertheless, clam ganglion esterase is sifficiently active to hydrolyze the physiological substrate, acetylcholine. These results explain the long-observed differences in isolated heart pharmacology between ostreid and venerid bivalves.


Factors affecting the uptake and metabolism of soluble carbohydrates by the rumen ciliate Dasytricha ruminantium isolated from ovine rumen contents by filtration. A filtration technique is described whereby metabolically-active suspensions of Dasytricha ruminantium can be isolated from rumen contents with negligible contamination by bacteria or other protozoa. The effects of environmental factors and of the diurnal cycle of the rumen on the uptake and metabolism of soluble carbohydrates by these isolated cells were examined. The principal contribution of the protozoan metabolic end-products to the host ruminant is the supply of lactic, acetic and butyric acids during periods when soluble sugars are in excess.


Production of phospholipase C (alpha-toxin), haemolysins and lethal toxins by Clostridium perfringens types A to D. To obtain high yields of extracellular enzymes and toxins for immunological analysis, type culture collection strains of Clostridium perfringens types A to D and 28 fresh isolates of C. perfringens type A from humans were grown in fermenters under controlled conditions in a pre-reduced proteose peptone medium. The type culture collection strains all showed different characteristics with respect to growth rates and pH optima for growth. Production of phospholipase C (alpha-toxin), haemolysin and lethal activity varied considerably between the different types. Growth and extracellular protein production in fermenters with pH control and static or stirred cultures were compared. Production of all extracellular proteins measured was markedly improved by cultivation in fermenters with pH control. Strain ATCC13124 produced five times more phospholipase C than any of 28 freshly isolated strains of C. perfringens type A, grown under identical conditions. Haemolytic and lethal activities of the ATCC strain were equal or superior to the activities of any of the freshly isolated strains. There were no differences in the bacterial yields and in the production of extracellular toxins between type A strains isolated from clinical cases of gas gangrene and abdominal wounds, and those isolated from faecal samples from healthy persons.


Role of wall phosphomannan in flocculation of Saccharomyces cerevisiae. Treatment with 60% hydrofluoric acid (HF) removed most of the phosphorus and small amounts of mannan, glucan and protein from walls of two non-flocculent strains (NCYC366 and NCYC1004) and two flocculent strains (NCYC1005 and NCYC1063) of Saccharomyces cerevisiae. Organisms of all strains showed increased flocculating ability following HF treatment. Flocculation  of untreated organisms of NCYC1005 and NCYC1063, and of HF-treated organisms of all four strains, declined appreciably when they were washed in deionized water, with or without EDTA, and the flocculation was measured in deionized water instead of in 0-05 M-sodium acetate containing Ca2+. Treatment with 1,2-epoxypropane also caused a decrease in the flocculating ability of these organisms. Extracting the lipids from organisms of strains NCYC366 and NCYC1004 had no effect on their flocculating ability, but decreased the flocculating ability of organisms of strains NCYC1005 and NCYC1063. pH-electrophoretic mobility curves of untreated and HF-treated organisms confirmed the loss of wall phosphate by HF treatment, and indicated that HF treatment had little effect on the content of protein carboxyl groups in the outer wall layers. Mannose at 0-22 M completely prevented floc formation by organisms of strain NCYC1063; but, even at 0-33 M, it had very little effect on floc formation by HF-treated organisms of strains NCYC366 and NCYC1063. Organisms of all four strains bound fluorescein-conjugated concanavalin A to the same extent after treatment with HF as before, but this treatment led to a greatly diminished binding of of fluorescein-conjugated antiserum raised against organisms of strain NCYC366. The results indicate that phosphodiester linkages in yeast-wall mannan are not involved in bride formation through Ca2+ during floc formation and that this arises principally through carboxyl groups.


Purification and characterization of phosphoglycerate mutase from methanol-grown Hyphomicrobium X and Pseudomonas AM1. Phosphoglycerate mutase has been purified from methanol-grown Hyphomicrobium X and Pseudomonas AMI by acid precipitation, heat treatment, ammonium sulphate fractionation, Sephadex G-50 gel filtration and DEAE-cellulose column chromatography. The purification attained using the Hyphomicrobium X extract was 72-fold, and using the Pseudomonas AMI extract, 140-fold. The enzyme purity, as shown by analytical polyacrylamide gel electrophoresis, was 50% from Hyphomicrobium X and 40% from Pseudomonas AMI. The enzyme activity was associated with one band. The purified preparations did not contain detectable amounts of phosphoglycerate kinase, phosphopyruvate hydratase, phosphoglycerate dehydrogenase or glycerate kinase activity. The molecular weight of the enzymic preparation was 32000 +/- 3000. The enzyme from both organisms was stable at low temperatures and, in the presence of 2,3-diphosphoglyceric acid, could withstand exposure to high temperatures. The enzyme from Pseudomonas AMI has a broad pH optimum at 7-0 to 7-6 whilst the enzyme from Hyphomicrobium X has an optimal activity at pH 7-3. The cofactor 2,3-diphosphoglyceric acid was required for maximum enzyme activity and high concentrations of 2-phosphoglyceric acid were inhibitory. The Km values for the Hyphomicrobium X enzyme were: 3-phosphoglyceric acid, 6-0 X 10(-3) M: 2-phosphoglyceric acid, 6-9 X 10(-4) M; 2,3-diphosphoglyceric acid, 8-0 X 10(-6) M; and for the Pseudomonas AMI ENzyme: 3-4 X 10(-3) M, 3-7 X 10(-4) M and 10 X 10(-6) M respectively. The equilibrium constant for the reaction was 11-3 +/- 2-5 in the direction of 2-phosphoglyceric acid to 3-phosphoglyceric acid and 0-09 +/- 0-02 in the reverse direction. The standard free energy for the reaction proceeding from 2-phosphoglyceric acid to 3-phosphoglyceric acid was -5-84 kJ mol(-1) and in the reverse direction +5-81 kJ mol(-1).


The effects of alkalinity and hypertonicity on the morphology and motility of Leptospira interrogans (biflexa) strain B16. Effects of alkalinity and hypertonicity on the motile behaviour of Leptospira interrogans (biflexa) B16 were observed, quantified, and compared with effects previously shown by similar factors on the motility of eubacteria. Leptospira interrogans tolerated relatively high concentrations of hydroxide ions. Motility similar to that in controls was observed at pH values up to 9-8; but at pH 10-0 motility declined sharply with time of exposure, and there was structural alteration, visible as a blebbing of the cell envelope. Unlike the behaviour of eubacteria, immobilization of L. interrogans induced by hydroxide ions could not be reversed by lowering the pH. It is suggested that by restricting entry of hydroxide ions, the cell envelope protects its motility apparatus from adverse effects. Leptospira interrogans was completely immobilized in 0-5 M and 1-0 M-sucrose solutions. Unlike the eubacteria, leptospires were incapable of spontaneous reversion to motile forms and resumption of motility was dependent on both concentration and time of exposure to sucrose. Deuterium oxide did not affect movement, suggesting that even though leptospire endoflagella and the exoflagella of eubacteria are analogous, the motile behaviour of L. interrogans is significantly different from that of eubacteria.


Autolysis in strains of viridans streptococci. Seven strains of viridans streptococci of the species Streptococcus sanguis, S. mutans and S. mitis were investigated for autolysis. The effect of pH, salt concentration and temperature on the autolytic process was studied in Na2HPO4/NaH2PO4 buffer. Whole cells and walls of all strains autolysed most rapidly at pH values above 7. Autolysis of whole cells of S. sanguis and one strain of S. mitis (ATCC15909) was maximal in 0-05 TO 0-2 M buffer, while the two S. mutans strains and S. mitis ATCC15912 showed maximal autolysis in 0-5 and 1-0 M buffers. Cultures harvested in the stationary phase of growth possessed only slightly decreased autolytic activity compared with those from the exponential phase. Whole cells autolysed more rapidly at 37 degrees C Than at 45 degrees C and 10 degrees C. Autolysis of isolated walls of three strains of S. mitis (ATCC903, ATCC15909 and ATCC15912) was maximal at pH 7-0 AND 7-5 and in 1-0 M buffers. Streptococcus mitis ATCC15909 also showed maximal lysis in 0-01 M and 0-5 M buffers. An endopeptidase action of the autolytic system of S. mitis ATCC15912 was indicated by the progressive release of soluble amino groups during autolysis of the walls. No release of reducing groups was observed. Several free amino acids were released during autolysis of these walls, alanine, lysine and glutamic acid being in greatest quanitity.


Antipsychotic drugs and dopamine-mediated responses in Aplysia neurons. The effect of antipsychotic drugs was tested on responses to micro-electrophoretically applied dopamine, acetylcholine and 5-hydroxytryptamine in identified neurons of the marine gastropod Aplysia californica. Fluphenazine was able to depress the response to DA in concentration of 10 muM, with 100 muM DA-responses of many neurons were blocked completely. Thioridazine (10 and 100 muM) and haloperidol (50 muM) were also effective in depressing DA-responses, while the non-antipsychotic phenothiazines mepazine (10 and 100 muM) and promethazine (100 muM) had only a slight action on DA-receptors. ACh- and 5-HT-responses were slightly affected only by high concentrations after long lasting perfusion. The investigated drugs had no persistent or only an insignificant effect on resting membrane potential and amplitude of action potentials of the neurons. With haloperidol depolarizing afterpotentials leading to double discharges were observed in some neurons. In a few instances spontaneous EPSPs disappeared with the DA-response under the influence of anti-psychotic drugs. The results render a direct neurophysiological evidence for the blockade of DA-receptors by antipsychotic drugs in correspondence to their clinical efficacy and agree with data from clinical observations and obtained in neurochemical, behavioral and indirect neurophysiological experiments.


N-substituted maleimide inactivation of the response to taste cell stimulation. N-Ethylmaleimide (NEM) irreversibly inactivates the response of gustatory cells to stimulation by NaCl, sucrose and hydrogen ions. The rate of inactivation can be measured by monitoring the decay of NaCl-stimulated summated electrophysiological activity at the chorda tympani nerve in the presence of NEM. The observed pseudo first-order rate constants are linear with NEM concentration, and the second-order rate constant is 0.38 M-1 sec-1. Other N-substituted maleimides, such as N-methylmaleimide and N-butylmaleimide, which have ether:water partition coefficient and is essentially ineffective as an inactivator of the NaCl response. These results, together with the observation that the inactivation rate is independent of pH between 4.5 and 7.0, indicate the inactivation site is either intracellular or buried within the cell membrane at a locus inaccessible to most extracellular fluids. The rate of inactivation of the sucrose and HCl responses were measured indirectly and found to be comparable to the NaCl-stimulated inactivation rate, indicating the inhibited event is common to the transduction of the response for all of the stimuli examined. Possible sites of inactivation by N-substituted maleimides are considered in the context for and characterizing receptor-specific as well as other classes of taste cell inhibitors.


Increased phosphorylated components of erythrocyte membrane spectrin band II with reference to Duchenne muscular dystrophy. Increased erythrocyte band II phosphorylation has been demonstrated in patients with Duchenne muscular dystrophy (DMD). Band II has been purified by preparative sodium dodecyl sulfate (SDS)-polyacrylamide gel electrophoresis. Isoelectric focusing of purified band II from which SDS has been removed reveals heterogeneity. Band II migrates as multiple bands on isoelectric focusing gels and as a single band on SDS-polyacrylamide gels. The increased phosphorylation in DMD does not occur uniformly in all components of band II. Highly phosphorylated components of band II are present in DMD in which only minimal phosphorylation occurs in controls. These results suggest the presence of an abnormal band II substrate in erythrocyte membranes from DMD patients.


The histochemical profile of the human masseter. An autopsy and biopsy study. A histochemical study has been carried out upon samples of muscle obtained from the human masseter. Sixteen specimens obtained either at autopsy or biopsy have shown that the middle and deep portions of the muscle contain fibres which in their size, histochemical staining properties and number correspond to the appearances noted in most human limb skeletal muscles. By contrast, samples taken from the superficial portion of the masseter demonstrated several unusual characteristics: these included a striking inequality of muscle fibre size in that the Type II fibres were much smaller than those of Type I but exceeded the latter in total number. This part of the muscle also contained, in 6 out of 10 samples, substantial numbers of intermediate fibres identified by myofibrillar ATPase staining. This study has confirmed that the superficial part of the human masseter is different morphologically and presumably functionally from the middle and deep parts of the muscle.


Effects of stock or purified diet on rat liver enzymes involved in the synthesis of dimethyl selenide. Rats fed either a stock deit or a purified diet based on casein were tested for their ability to convert 75Se-sodium selenite to volatile selenium (dimethyl selenide) in vivo. This conversion was also studied in liver and kidney in vitro. When injected with a subacute dose of selenite (2 mg Se/kg), rats previously fed stock diet volatilized more than twice as much of the dose compared to rats fed the purified diet, confirming earlier findings. Parallel dietary effects were also observed in vitro using subcellular fractions incubated with 75Se-selenite, glutathione, TPNH, and S-adenosylmethionine. The 9-000 X g supernate prepared from rats fed stock diet synthesized dimethyl selenide at approximately twice the rate of that prepared from rats fed purified diet. A fourfold higher activity was observed with liver microsomal fractions from rats fed the stock diet, whereas cytosol was slightly more active in rats fed the purified diet. Kidney fractions showed analogous changes with diet, although the activity of kidney microsomal fraction was very low. Only minor differences in the levels of glutathione reductase, nonspecific disulfide reducatse, and non-protein thiols were observed in liver and kidney from rats fed the two diets. Considering the effects of diet on the various enzymes known from our previous studies to be involved in dimethyl selenide synthesis, it was concluded that the enhanced ability of rats fed stock diet to synthesize dimethyl selenide results from the induction of a liver microsomal enzyme, apparently a Se-methyltransferase, caused by unknown substances in the stock diet.


Nitrogen intake and tumorigenesis in rats injected with 1,2-dimethylhydrazine. Tumor incidence was studied in 1,2-dimethylhydrazine (DMH) injected male rats assigned at weaning to isoenergetic casein-sucorse deits containing 7.5%, 15%, or 22.5% protein with or without 2.5% urea. Twenty rats fed each diet were given weekly intraperitoneal injections of DMH (15 mg/kg body weight/week) for the first 24 weeks and 20 were given saline. Of 96 DMH-injected rats necropsied after 28 weeks, 88 were necropsied during the 32nd or final week of the experiment. Adenocarcinomas of the small and large intestine were larger and significantly more numberous in rats fed 15% and 22.5% dietary protein. Keratin producing papillomas of the sebaceous glands of the external ear were observed first at 21 weeks in DMH-injected rats fed 22.5% protein. These were subsequently observed in some rats from all DMH-treated groups. As time progressed, the ear tumors increased in size and number in all groups but the greatest incidence was in the group fed 22.5% protein. No tumors were observed in saline-injected rats. Urea feeding did not increase the number of tumors nor cause changes in pH, urease activity or ammonia concentration of contents of the colon or cecum, or blood cholesterol. As dietary protein increased, cecal ammonia concentrations rose while both colon and cecal pH dropped. Portal blood urea and cholesterol reose as dietary protein was increased. DMH-treated rats had significantly higher concentrations of colon and cecal ammonia and lower blood cholesterol. Altough the rats fed 7.5% protein gained significantly less weight during 0 to 6 weeks of feeding, their weight gain was significantly higher during 6 to 26 weeks. No tumors were found in rats necropsied at 16 weeks.


Digestion and absorption of bovine milk xanthine oxidase and its role as an aldehyde oxidase. The effects of acidic and intestinal proteolytic environments on bovine milk xanthine oxidase (XO) activity were determined in order to evaluate the extent to which this enzyme was absorbed in biologically active form. The inhibition of XO by folic acid and the relative affinities of XO for the oxidation of palmitaldehyde, stearaldehyde, and xanthine were compared. The effects of acid and gastric juice on XO activity were measured by incubating purified enzyme, and non-purified enzyme (milk), in buffers ranging in pH from 2 to 9. Fresh gastric juice was also incubated with milk. Increasing amounts of the enzyme were inactivated as the pH of the incubation mixture was reduced below pH 6.5. Below pH 3.5, the enzyme was completely inactivated. Gastric juice, pH juice incubated with milk. Milk XO activity was reduced 36% when mild was incubated with an equal volume of gastric juice. Homogenized milk had 59% less XO activity compared with raw molk. Fresh raw milk XO, homogenized milk XO, and purified XO were equally susceptible to inactivation by acid or gastric juice. After incubation of milk with gastric juice, or gastric juice followed by pancreatin, XO activity was associated with a macromolecule of 300,000 daltons molecular weight and subunits containg activity were not found. It was estimated that 0.00008% of the XO in the intestine was absorbed. Both folic acid and allopurinol inhibited XO activity in vitro. Allopurinol was 3.5 times more potent an inhibitor than folic acid. A large excess of dietary folic acid did not reduce rat liver or intestinal XO activity in vivo. XO had a much greater affinity for xanthine than for palmitaldehyde or stearaldehyde substrates. It was estimated that of 100 mg of XO in fresh raw milk, 41 mg remained after homogenization, 27 mg entered the intestine and only 20 ng were absorbed as intact enzyme.


The formation of a platelet adhesive factor by disruption of the creatine phosphokinase molecule. It was discovered that the product of a mix containing the enzyme creatine phosphokinase (CPK) and either glutathione (GSH) or cysteine caused platelets to adhere together in vitro. This platelet adhesive factor (PAF) was formed as CPK enzyme activity declined. An alternative method for the destruction of enzyme activity--heat at 56 degrees C--also resulted in the formation of an in-vitro active PAF which was both less stable and active than its chemically produced counterpart. Assay of the platelet adhesive potency of the CPK-GSH mix, using human platelets, revealed a wide variation in the response of different individuals' platelets to standard quantities of PAF. The nature of this preparation of PAF was investigated by both biochemical and biophysical means, including ion exchange chromatography, electrophoresis, amino acid analysis and analytical ultracentrifuge studies. Evidence is presented that PAF is the product of the disruption of the dimeric structure of the CPK molecule. PAF was found to adhere to paper, under the conditions of electrophoresis imposed, and also to cause sephadex beads to bind together, characteristics which suggested that the platelet adhesion reaction was probably a biophysical process. Red and white cells were not similarly affected. The feasibility of this novel concept for the initiation of platelet adhesion, as a naturally occurring process, was supported by the results of animal experiments in which a statistically depression of platelets in the systemic circulation followed the intravascular administration of PAF. The possible relevance to man of this basic mechanism in relation to exercise and disease processes, including ideopathic and post-traumatic thrombosis, atherogenesis, and dysbaric aseptic necrosis of bone, is discussed.


Proteinase activity in Ascaris suum eggs, hatching fluid, and excretions-secretions. Hatching fluid and the excretions and secretions (E.S.) of hatched larvae of Ascaris suum revealed proteinase activity when assayed by 2 different procedures employing collagen or casein as substrates. Both assays apparently detected similar levels of proteinase activity in hatching fluid and E.S. of hatched larvae. The Anson (casein substrate) assay worked best in 0.05 M phosphate buffer, pH 8.0. The Azocoll (collagen substrate) assay worked best in 0.05 M borate buffer at pH 8.8. Azocoll assays done at temperatures ranging from 25 to 65 C revealed maximal proteinase activity at 55 C. Analysis of hatching fluid from 18-, 21-, and 28-day-old embryos and of extracts from sonicated 0- to 28-day-old developmental stages showed that proteinase activity increased markedly 18 days after embryonation had begun. Prior to the 18th day of embryonation proteinase levels were relatively low.


Prostaglandins and leucotaxis.

Prostaglandins and leucotaxis. Freshly prepared solutions of prostaglandin E1 exhibit chemotactic activity against rabbit polymorphonuclear leucocytes harvested from the peritoneal cavity but are devoid of such activity either against similar cells obtained from the rat or against polymorphonuclear leucocytes obtained from the blood of the rabbit, rat and man. Some implications of these findings with respect to the development of inflammatory responses and the mode of action of non-steroidal acidic anti-inflammatory drugs are discussed.


Pharmacological studies with adenine, adenosine and some phosphorylated derivatives on guinea-pig tracheal muscle. Adenine, adenosine and three adenine nucleotides all caused relaxation of the guinea-pig trachea. The relaxation to the nucleotides was often preceded by a contraction. The response to adenosine and the nucleotides, but not adenine, was potentiated by dipyridamole. Imidazole inhibited the response to adenine alone. Propranolol has no effect on the response to any of the compounds. It is concluded that the guinea-pig trachea does not possess and a nucleotide-specific receptor as has been postulated for some other smooth muscle preparations. An alternative hypothesis postulating an adenosine-specific receptor is presented.


Interactions of bradykinin, prostaglandin E1, 5-hydroxytryptamine, histamine and adenosine-5'-triphosphate on the dry leakage response in rat skin. Dye leakage in rats produced by intracutaneous injections of irritants was quantitated using an azovan blue technique. Concentration-response lines were obtained for irritants alone and in presence of constant concentrations of other irritants. 5-Hydroxytryptamine (5-HT) (10-7M) potentiated histamine, bradykinin and prostaglandin E1 (PGE1) but inhibited adenosine-5'-triphosphate (ATP). Histamine (10-5M) potentiated bradykinin, PGE1 and ATP. Bradykinin (10-6M) potentiated PGE1 only, but PGE1 (10-6M) potentiated bradykinin, 5-HT and histamine. ATP (10-4M) potentiated 5-HT, histamine and PGE1. Release of ATP during stimulation of sensory nerves might explain enhanced neurogenic oedema observed in skin surrounding an area pretreated with compound 48/80.


Polymorphism of disopyramide.

Polymorphism of disopyramide. Two crystal forms of disopyramide have been characterized using X-ray diffraction, differential scanning calorimetry and infrared spectroscopy. The kinetics of the solid state transformation of Form I to Form II has been analysed using the Prout-Tompkins theory. An activation energy of 144 kJ mol-1 is calculated for the system. Dissolution and plasma concentrations show no significant differences in bioavailability between the two polymorphs.


Aggregation of antiacetylcholine drugs in aqueous solution: monomer concentrations in non-micellar drug systems. The self-association of the antiacetylcholine drugs, propantheline bromide, methantheline bromide and methixene hydrochloride in aqueous solution, has been examined by surface tension, light scattering and conductimetric methods. Surface tension graphs were similar to those of conventional surfactants, showing apparent critical micelle concentrations (cmc) at distinct inflection points. Surface tension measurements in the presence of increasing amounts of electrolyte indicated a decrease in the apparent cmc with increase in electrolyte concentration for propantheline bromide. Light scattering curves for propantheline bromide in electrolyte solution showed no significant discontinuity attributable to a cmc. A mode of self association involving aggregate growth by the stepwise addition of monomers was assumed and equilibrium constants for the initial stages of the association were evaluated. An increase in the magnitude of the stepwise association constants with increase in electrolyte concentration was noted. Integration of the light scattering data according to 1n x = oo [(M/Mapp) - 1] dln c (where M and M app are the monomer and apparent aggregate weights respectively and x is the weight fraction of monomers) showed an asymptotic increase in monomer concentration towards a limiting concentration, as the solution concentration, c was increased. Limiting monomer concentrations determined by this method were in reasonable agreement with the apparent cmcs from surface tension studies. It was not possible to detect a cmc for methantheline or propantheline bromide from conductivity measurements.


Stability of salicylamide-caffeine complex at different temperatures and its thermodynamic parameters. The stability constants for formation of complexes of salicylamide with caffeine have been measured between 15 and 45degrees, by means of the solubility method. There was a linear solubility increase at all temperatures but phase diagrams indicated that at 15 and 25degrees an additional phase was formed which was found to be an insoluble 1 : 1 complex. The enthalpies and entropies of interactions were evaluated. They indicate that the interaction is exothermic and enthalpy controlled.


5-Hydroxytryptamine is a substrate for both species of monoamine oxidase in beef heart mitochondria. The activity of beef heart mitochondrial monoamine oxidase towards 5-hydroxytryptamine (5-HT) is inhibited by the selective inhibitors clorgyline, PCO [5-phenyl-3-(N-cyclopropyl)-ethylamine-1,2,4-oxidiazole] and Deprenyl with a biphasic dependence on the inhibitor concentration. The activities towards tyramine, dopamine and tryptamine were also inhibited in a biphasic manner, but the apparent proportions of the two enzyme species active on dopamine and tryptamine depended on the inhibitor used. Phenethylamine oxidation was inhibited in a monophasic manner suggesting that only a single enzyme species was responsible for the oxidation of this substrate. The biphasic response of 5-HT oxidation to inhibition by clorgyline persisted when functionally competent mitochondria were used and was unaffected by the soluble amine oxidase inhibitors semicarbazine and aminoguanidine. These results indicate that the behaviour of the beef heart enzyme towards selective inhibitors is considerably different from that of any preparations previously studied and suggest that the classification of monoamine oxidase activites into A and B types may be only of limited usefulness.


Bioanalysis of picomole amounts of acetylcholine by ion-pair partition chromatography applied to rat sciatic nerve. A method for determination of acetylcholine in small, discrete biological objects by use of ion-pair technique has been developed. Acetylcholine is extracted as an ion pair with 3,5-di-t-butyl-2-hydroxybenzenesulphonate and separated from co-extracted components by ion-pair partition chromatography with picrate as the counter ion and porous cellulose as support. The quantitative evaluation is made from the acetylcholine peak in the chromatogram obtained by ultraviolet detection. Acetylcholine has been analysed in 1 cm large pieces of rat sciatic nerve containing about 60 pmol (10 ng). The overall recovery of the method is 100 +/- 10% at the 120 pmol level of acetylcholine in a sample.


The effects of administering N-(2-benzoyloxyethyl) norfenfluramine to rats on the hepatic synthesis of glycerolipids. N-(2-Benzoyloxyethyl) norfenfluramine (S-780) was administered to rats by stomach tube at a dose of 50 mg kg-1 of body weight. Livers of the rats which were given an acute dose of the drug synthesized more triacylglycerol, phosphatidylcholine and phosphatidylethanolamine from [1,3-3H]glycerol and [14C]palmitate than did those of control rats. The measurements were made by injecting a mixture of the radioactive precursors into the portal veins of anaesthetized rats and freeze clamping a portion of the liver 1 min later. Diffferent results were obtained after treating rats daily with S-780 for 5 days. Liver slices from these rats synthesized less triacylglycerol and relatively more phosphatidylinositol plus phosphatidylserine from [3H]glycerol than did those of control rats. S-780 treatment depressed the hepatic synthesis of phosphatidylcholine and phosphatidylethanolamine as measured in vivo after intrapotal injection of [14C]palmitate and [3H]glycerol. Chronic treatment with S-780 also depressed food intake and lowered liver weight and body weight of rats fed the 41B diet. The results are discussed in relation to the effects of S-780 on the synthesis of glycerolipids.


Influence of various substances on prostaglandin biosynthesis by guinea-pig chopped lung. Guinea-pig chopped lung tissue was used to investigate the inhibitory effect of various steroidal and non-steroidal anti-inflammatory agents, antipyretics, analgesics, local anaesthetics and psychotropic drugs on mechanically induced release of prostaglandin-like material. Low concentrations of non-steroidal anti-inflammatory agents inhibited synthesis, but other antipyretics and analgesics, and the local anaesthetics had little effect. Thymoleptics, neuroleptics and monoamine oxidase inhibitors except phenelzine exhibited weak activity. It is concluded that the method is a useful pharmacological model to study prostaglandin biosynthesis. The weak effects of the psychotropic drugs suggest that they do not exert their clinical effect by inhibiting PG biosynthesis.


Metabolic N-oxidation of atropine, hyoscine and the corresponding nor-alkaloids by guinea-pig liver microsomal preparations. Incubation of guinea-pig liver microsomal preparations with atropine or hyoscine resulted in the formation of the corresponding nor-alkaloids and both isomers of atropine N-oxide from atropine and one isomer of hyoscine N-oxide from hyoscine. Separate incubations of guinea-pig liver microsomal preparations with nor-atropine and nor-hyoscine yielded the corresponding hydroxylamines. The N-oxide and hydroxylamine metabolites were identified by comparison of their t.l.c. behavior and m.x. with prepared compounds and also by their reduction to the corresponding tertiary or secondary amines.


The microsomal N-oxidation of phentermine. The microsomal N-oxidation of phentermine (Ia) to N-hydroxyphentermine (Ib) and to alpha,alpha-dimethyl-alpha-nitroso-beta-phenylethane (Ic was investigated. Maximum activities were obtained with microsomal (9000 g supernatant and microsomes) fractions of rabbit liver in the presence of an NADPH generating system. Incubation of Ia with hepatic washed microsomes from a phenobarbitone pretreated rabbit increased the formation of Ib and decreased that of Ic but the total amount of N-oxidized metabolites (i.e. Ib + Ic) was not affected. The ratio of the metabolically produced Ic to Ib but not the total amount of N-oxygenated metabolites varied greatly depending of the liver microsomal fractions used in the incubation mixtures of Ia; more Ib was produced from Ia using 9000 g supernatant and conversely, more Ic was formed using the washed microsomes of the same liver. The nitroso compound (Ic) was metabolically reduced to Ib and Ib to Ia by the hepatic 9000 g supernatant and soluble fraction; under the same conditions, washed microsomes had only limited reductive properties towards Ic and Ib. N-Hydroxyphentermine (Ib) was not metabolically oxidized to Ic when incubated with washed microsomes from rabbit liver. The use of known carbon-oxidation inhibitors showed that cytochrome P-450 is not involved in the incorporation of oxygen at the nitrogen centre of Ia. The metabolic characteristics and kinetic behavior of the microsomal N-oxidation of Ia supported a recently proposed mechanism explaining the independent formation of Ib and Ic from a common precursor resulting from metabolic N-oxidation of Ia.


A new class of irreversible muscarinic antagonists: beta-haloethylamine furoates. The synthesis of a class of ultra-long acting muscarinic antagonists is described. Furthermore, it is noted that the stability of the, in situ, aziridinium ion is sufficiently great so that these agents can be used to study the effect of temperature upon the conformation of the muscarinic cholinoceptor. The inactivation kinetics of these receptors as well as the dissociation constants, Kd, for all probes are presented.


The influence of polyvinylpyrrolidone on the solution and bioavailability of hydrochlorothiazide. The dissolution properties of hydrochlorothiazide-PVP 10 000 mechanical mix and coprecipitate systems were qualitatively similar to those previously reported using hydroflumethiazide. Quantitative differences were dependent on the proportion of PVP present, its molecular weight and method of incorporation. Cumulative urinary excretion data from test capsule preparations showed that bioavailability was enhanced by the presence of PVP. However, the degree of enhancement was less than that expected from constant surface area disc rate studies. Dissolution tests on the capsule formulations, using the U.S.P. basket stirrer assembly, did not correlate with in vivo results. Using the Levy beaker method and a stirring speed of 40 rev min-1, good correlation between amount dissolved in 30 min and amount excreted in urine after 24 h was obtained. The dissolution tests revealed that PVP retards the initial dissolution from capsule dosage forms, probably by retarding deaggregation and dispersion of drug particles.


Data point weighting in pharmacokinetic analysis: intravenous paracetamol in man. Compartmental analysis of plasma paracetamol concentrations following intravenous injection of 12 mg kg-1 in aqueous solution to normal subjects was performed using analogue and digital computer methods. Using a "simplex" non-linear optimization procedure, the pharmacokinetic parameters were found to be influenced considerably by the choice of the weighting factors (W1) attributed to individual data points. The plasma half-life of paracetamol varied by up to a seven-fold with the weighting factors selected. However, the predicted mean steady-state plasma concentrations were shown to be relatively little affected by the different weighting factors.


Electrochemistry of drug action I: electrooreduction of ferredoxins. Ferredoxin serves as an electron carrier in the oxidation-reduction system in anaerobic microorganisms, transferring electrons from a low potential donor to electron-accepting biochemicals. The anaerobicidal activity of some drugs may be due to their interference with the electron transport function of ferredoxin. Two types of ferredoxins (isolated from Clostridium pasteurianum and spinach) were studied, and their electrochemical reduction and biochemical properties were analyzed using a sensitive ac polarographic technique. The reduction potential of both ferredoxins was linearly related to pH. The mechanisms of electron transport in ferredoxin molecules were found to be related to their sulfur-iron bonds. The dissociation of the sulfur-iron bonds resulted in the formation of a free sulfhydryl group and the interruption of the electroactivity of ferredoxin. This sulfur-iron dissociation process was found to be pH dependent. The electroreduction of ferredoxins was an energy-requiring, pH-dependent process.


Liquid chromatography in pharmaceutical analysis V: determination of an isoniazid-pyridoxine hydrochloride mixture. Operating parameters are described for the qualitative and quantitative analysis of an isoniazid-pyridoxine hydrochloride mixture by high-pressure liquid chromatography. Each compound was chromatographed on an octadecyl column, using absolute methanol-water (60:40) (pH 2.5) containing 0.01 M dioctyl sodium sulfosuccinate. The flow rate was 2.0 ml/min (2500 psig), and the peaks were detected at 293 nm. The analysis was accomplished using ion-pair formation for effecting chromatographic separation. The time required for separation of the drug mixture is approximately 12 min with an accuracy of 1.17-0.30%.


Simple and rapid determination of a new pharmaceutically active amine hydrochloride. The quantitative analysis of a new pharmaceutically active amine hydrochloride is described. Samples are extracted with chloroform. A yellow amine-dye complex is formed by buffering a sample-bromthymol blue solution at pH 8.5 +/- 0.1 and subsequently extracted with chloroform. The complex is treated with 0.01 N NaOH to convert it back to the sodium salt of bromthymol blue, which is then measured at 615 nm in the aqueous layer. The amount of complex extracted is linearly related to the amount of amine present, from 0.020 to 0.20 mg/ml. Under the selected conditions, the compound can be determined in the presence of degradation products and there is no interference from common pharmaceutical excipients. The method is suitable for stability studies.


Phenylbutazone ionization kinetics.

Phenylbutazone ionization kinetics. Phenylbutazone has been associated with bioavailability problems and has shown nonclassical behavior in phase-transport studies. This nonclassical behavior has been attributed, in part, to the fact that phenylbutazone, as a carbon acid, undergoes noninstantaneous ionization kinetics. Instantaneous reaction is an assumption made in many diffusion-limited transport models involving a simultaneous ionization reaction. The ionization kinetics of phenylbutazone were determined at an ionic strength of 0.1 and 25 degrees using a stopped-flow spectrophotometer. A log kobs versus pH profile for the approach to the ionization equilibrium was determined, and a mechanism consistent with the profile was postulated. The percent enol versus the diketo form of phenylbutazone acid as well as pKaenol and pKadiketo was kinetically calculated. The protonation reaction was highly catalyzed by general acids while the deprotonation reaction was highly catalyzed by general bases. The general acid, water, was a poor proton donor to the anionic form (the so-called mesomericanion) of phenylbutazone.


Conversion of cefamandole nafate to cefamandole sodium. The rate of hydrolysis of the formyl moiety of cefamandole nafate was determined as a function of pH, temperature, and concentration of added sodium carbonate or tromethamine. The reaction rate was sensitive to hydroxide ion in the pH 5.5-8.0 range with half-life values of hours to minutes. Hydrolysis was rapid upon the addition of sodium carbonate or tromethamine. Chirality in the 7-D-mandelamido side chain was unaffected by hydrolysis.


Structure of aluminum hydroxide gel I: initial precipitate. The initial aluminum hydroxide gel precipitate resulting from the reaction of aluminum chloride or aluminum sulfate with ammonium hydroxide is shown by potentiometric titration, chemical analysis, and the ratio of bound hydroxide to aluminum to fit a polymer model described previously. The formation of polynuclear hydroxyaluminum particles is treated as a stepwise process involving a deprotonation-dehydration mechanism, which results in the formation of six-membered rings; these rings may further coalesce by the same mechanism. The aluminum hydroxide gel precipitated from aluminum chloride can be represented by the formula Al(OH)2.55(Cl)0.45 and probably exists as a polymer of 10 fused six-membered rings. The aluminum hydroxide gel precipitated from aluminum sulfate can be represented by the formula Al(OH)2.30(SO4)0.35. This species probably exists as a polymer of three fused six-membered rings.


Structure of aluminum hydroxide gel II: aging mechanism. The aging of aluminum hydroxide gel prepared by the reaction of aluminum chloride and ammonium hydroxide was studied by measurement of pH, acid-consuming capacity, hydroxide to aluminum ratio, chloride activity, and X-ray line broadening. The results were consistent with a polymer model involving particle growth by a deprotonation-dehydration mechanism. Anions inhibit this reaction by binding to the positively charged edges of the hydroxyaluminum polymers.


Structure of aluminum hydroxide gel III: mechanism of stabilization by sorbitol. The effect of sorbitol on the aging of aluminum hydroxide gel, prepared by the reaction of aluminum chloride solution with strong ammonia solution to a final pH of 7.0, was studied by potentiometric titration, acid-consuming capacity, pH, hydroxide to aluminum ratio, chloride activity, X-ray diffraction, and IR spectroscopy. Gels containing sorbitol lost less than 10% of their acid-consuming capacity during a 6-month aging period compared with a loss of more than 60% for an identical gel without sorbitol. The mechanism by which sorbitol stabilizes the gel appears to be inhibition of the secondary polymerization reaction which takes place upon aging. Another polyhydroxy compound, quercetin, also stabilizes aluminum hydroxide gel.


Kinetics and mechanisms of hydrolysis of 1,4-benzodiazepines I: chlordiazepoxide and demoxepam. Differential absorbance spectroscopy was successfully used to follow the hydrolysis kinetics of chlordiazepoxide and demoxepam from pH 1 to 11. Loss of the methylamino group from chlordiazepoxide produced demoxepam. Demoxepam degraded by a parallel consecutive reaction to 2-amino-5-chlorobenzophenone and a glycine derivative. Two intermediates were observed by TLC for demoxepam hydrolysis. One was assigned the open-ring structure resulting from amide hydrolysis, which kinetically appears to be the major mechanistic route leading to the benzophenone product. The other intermediate, representing an alternative but minor pathway, presumably results from initial scission of the azomethine linkage. Protonation of the N-oxide slightly alters the importance of these two pathways. Recyclization of the carboxylic acid intermediate was facile at pH values below the pKa of this intermediate. The stability parameters involving buffer catalysis, ionic strength effects, and temperature dependence of rate constants are reported.


Spectrofluorometric determination of hydroflumethiazide in plasma and urine. A rapid, accurate, sensitive, and reproducible assay for hydroflumethiazide in plasma and urine was developed after studies of its UV and fluorescence spectral properties and partitioning behavior. The assay is based on initial extraction from acidified plasma or urine into ether, back-extraction into basic solution followed by acidification to about pH 1, and measurement of the fluorescence derived from the unionized molecule. Analysis of variance indicated no significant differences in assays performed on the same day. The mean recovery was 98.8 +/- 7.4% for plasma over a concentration range of 0.2-2.0 mug/ml. The method is convenient for routine clinical use and has sufficient sensitivity to quantify hydroflumethiazide levels after administration of therapeutic doses.


Spectrofluorometric determination of bufuralol in blood and urine. The benzofuran analog bufuralol, a beta-adrenergic blocker, was determined in blood and urine by a specific and sensitive spectrofluorometric assay. The compound was extracted into ether from blood or urine adjusted to pH 10. The ether extract was separated by TLC to resolve the parent drug from any basic metabolites present, and the spots were eluted off the silica gel and quantitated fluorometrically in 0.1 N HCl. The overall recovery of the assay was 85 +/- 3.0%; the sensitivity limit was 2-4 ng/ml of blood or urine, using a 2.5-ml specimen/analysis. The method was applied to the determination of blood levels in a dog following a single 10-mg/kg oral dose and in two human subjects administered a single 20-mg oral dose.


Kinetics of acid neutralization by aluminum hydroxide gel. The rate of acid neutralization by an aluminum hydroxide gel prepared by the reaction of aluminum chloride solution and strong ammonia solution was studied. The decrease in acid-consuming capacity during aging as measured by the USP test is due to a decrease in the rate of reaction rather than to a decrease in equilibrium reactivity. The reactivity profile has three phases, which are shown to be related to the structure of the gel. The rate of loss of reactivity is directly related to the extent of washing.


Effect of histamine and antihistamines on renal hemodynamics and functions in the isolated perfused canine kidney. Histamine was infused intra-arterially (10-40 mug/min) into isolated blood perfused canine kidneys while functional and hemodynamic parameters were monitored. When perfusion pressure (PP) was kept constant during the infusion of histamine, renal blood flow (RBF) increased from 137 +/- 9 to 181 +/- 9 ml/min (P less than .001). A greater increase in RBF occurred to the inner renal cortex than the outer renal cortex as measured by radioactive microspheres. The fractional outer/inner cortical blood flow changed from 79:21 before histamine to 74:26 during its infusion (P less than .001). Histamine did not alter creatinine clearance (Ccr), urine volume (V), sodium excretion (UNaV) or the fractional excretion of sodium (FENa) or water (FEH20) under these conditions. When renal blood flow was held constant during the infusion of histamine, PP decreased from 126/106 +/- 2 to 100/81 +/- 2 mm Hg (P less than .001). This resulted in a reduction of absolute outer cortical (outer/inner) changed from 77:23 before histamine to 72:28 during its infusion (P less than .001). In contrast to the effects of histamine at constant PP, CCr, V, UNaV, FENa, and FEH20 were decreased when histamine infusion reduced the PP. Administration of the H1 receptor antagonist, diphenhydramine, blocked the hemodynamic effects of histamine whereas the administration of an H2 receptor antagonist, metiamide, did not alter the histamine response. Similar vasodilatory responses to histamine were observed in isolated blood perfused dog and cat kidneys. In contrast, vasoconstrictor responses to histamine occurred in isolated dog and cat kidneys perfused with Krebs' solution and in isolated rabbit kidneys whether perfused with blood or Krebs' solution.


Phenacetin: renal tubular transport and intrarenal distribution in the dog. In a total of 22 studies in the anesthetized dog, the renal clearnace of phenacetin was measured over a range of plasma concentrations and at different urinary pH and rates of urine flow. Phenacetin is reabsorbed by passive diffusion. The urine/plasma ratio is essentially unity under all conditions. As measured by ultraviolet-spectrophotometric and colorometric methods and by high-pressure liquid chromatography, a labile metabolite appears in urine and renal papilla which upon hydrolysis gives rise to falsely high values for phenacetin. Renal cortical and papillary concentrations were determined in six dogs during hydropenia or diuresis. All tissue/plasma concentration ratios for phenacetin were essentially unity. The results indicate that the papillary localization of the earliest lesions of analgesic nephropathy cannot be attributed to high phenacetin concentrations within the papilla. This is in contrast to acetaminophen, the major metabolite of phenacetin.


Loperamide binding to opiate receptor sites of brain and myenteric plexus. Loperamide, a new antidiarrheal agent, was tested to determine whether its biological activity involves binding to opiate receptor sites. Loperamide and morphine competitively inhibited 3H-naloxone binding to homogenates a guinea-pig brain and myenteric plexus. The Kp values obtain in the presence of Na+ were: morphine, 9.60-10(-9) M (brain), 1.66-10(-7) M (myenteric plexus); loperamide, 7.20-10(-9) M (brain), 1.33-10(-7) M (myenteric plexus); naloxone, 4.78-10(-10) M (brain), 1.27-10(-9) M (myenteric plexus. In the absence of Na+, binding a loperamide and morphine to brain homogenate was enhanced while the binding of naloxone was reduced. Morphine (IC50 = 7.5-10(-8) M) and loperamide (IC50 = 6.9-10(-9) M) inhibited the electrically induced contractions of longitudinal muscle from guinea-pig ileum, and naloxone competitively antagonized these effects. The Kd value calculated for the interaction of naloxone with binding sites associated with the contracting muscle was between 0.98-10(-9) M and 1.85-10(-9) M. In the mouse hot plate test, subcutaneous administration of morphine (minimal effective dose = 6.6 mugmol/kg) and loperamide (minimal effective dose = 78 mugmol/kg) delayed the response to heat stimuli and this effect was completely blocked by prior administration of naloxone. In the anesthetixed dog, intravenous administration of morphine (100 mug/kg) and loperamide (100 mug/kg) enhanced the contractile activity of circular muscle in proximal and distal duodenum, distal ileum and proximal colon but duodenal longitudinal muscle was relaxed; these effects were completely reversed by subsequent administration of naloxone. It is concluded that loperamide binds to opiate receptor sites and possesses opiate agonist activity both in vivo and in vitro.


Cellular mechanisms of renal tubular transport of I-dopa and its derivatives in the rat: microperfusion studies. Proximal tubular transport of L-3,4-dihydroxyphenylalanine (L-dopa) and its derivatives were studied in the rat kidney by microperfusion and capillary perfusion techniques in situ. With the use of microperfusion techniques alone, it was found that L-dopa, L-3-methoxy-4-hydroxyphenylalanine, L-tyrosine and L-phenylalanine rapidly disappeared from the perfusate. The rates of reabsorption were calculated to be 2.05 X 10(-12), 2.13 X 10(-12), 6.35 X 10(-12) and 7.14 X 10(-12) mol/cm/sec, respectively. In contrast, L-alpha-methyldopa and dopamine were only slightly reabsorbed. The permeability coefficients were calculated to be 0.35 X 10(-4) and 0.21 x 10(-4) and 0.21 x 10(-4) cm/sec, respectively. The rate of reabsorption of L-dopa was greatly reduced in the presence of L-phenylalanine in the perfusate, but was not affected by D-dopa. With the stop-flow microperfusion technique with simultaneous capillary perfusion, the zero net flux transtubular concentration difference (deltaC) of labeled dopa was measured. When the initial concentration of 2 mM labeled L-dopa was perfused, the luminal concentration fell to a plateau level of 1.5 mM after a contact time of 20 seconds; i.e., deltaC was 0.5 mM. The net flux was much less than the efflux, suggesting the presence of a secretory or passive back flux of L-dopa. The deltaC of L-dopa was not influenced by the decarboxylase inhibitor, MK-486, and monoamine oxidase inhibitor, pheniprazine, but was significantly reduced by NaCN. Thus the reabsorption of L-dopa in the proximal convoluted tubule is an active process with great structural specificity.


Biosynthesis and metabolism of endogenous tyramine and its normal presence in sympathetic nerves. By use of a sensitive and specific enzymatic isotopic method for the determination of tyramine, the small quantities of this amine which are present endogenously in rat tissues, including brain, heart, kidney and salivary gland, have been quantitated. The levels of tyramine in brain were increased to a similar extent by injecting animals with a monoamine oxidase inhibitor, pargyline, and a dopamine beta-hydroxylase inhibitor, FLA-63; in contrast, pretreatment of animals with alpha-methyl-para-tyrosine, a tyrosine hydroxylase inhibitor, did not lead to an increase in tyramine levels in brain. Pretreatment of rats with 6-hydroxydopamine resulted in a marked diminution in the tyramine content of rat atria and salivary gland. Denervation of the salivary gland decreased the endogenous level of tyramine approximately 50% in denervated glands compared to undenervated glands. These results suggest that tyramine exists at least partly in sympathetic nerves in many tissues.


The beta adrenergic receptors of chromatophores of the frog, Rana pipiens. The isolated skin of Rana pipiens was found to be a suitable model for the quantitative study of chromatophore beta adrenergic receptors uninfluenced by prejunctional phenomena. Cumulative concentration-response curves for adrenergic agonists were obtained in preparations in which effective alpha adrenergic blockade had been produced with phenoxybenzamine. The beta adrenergic agonists darkened the preparation, as did melanocyte-stimulating hormone, but the maximum effects differed. The maximum of the l-isoproterenol cumulative concentration-response curve was  approximately 50% less than that of melanocyte-stimulating hormone, while the maxima for l-epinephrine and l-norepinephrine were significantly less than that for isoproterenol. Microscopic examination revealed a qualitative difference: while maximal darkening produced by melanocyte-stimulating hormone was associated with maximal changes in both interspot melanophores and iridophores, maximal adrenergic-induced darkening was associated with maximal iridophore granule concentration only. No qualitative differences could be observed in the darkening caused by the three adrenergic agonists. The beta adrenergic potencies of l-norepinephrine and l-isoproterenol relative to l-epinephrine were determined by four-point bioassay. Isoproterenol was found to be 138 times as potent as epinephrine, while norepinephrine was 4 times as potent. Similarly, antagonism of isoproterenol-induced darkening of phenoxybenzamine-pretreated skin samples by the beta adrenergic blocking agents dl-propranolol, dl-sotalol, dl-practolol, l-butoxamine and d-butoxamine was studied, and their KB and pA2 values, respectively, were found to be: dl-propranolol (1.44 X 10(-8)M, 7.81); dl-sotalol (7.25 X 10(-8)M, 7.23); l-butoxamine (6.92 X 10(-6)M, 5.10); dl-practolol (1.91 X 10(-5)M, 4.96); d-butoxamine (no activity). Comparison of the potency ratios and pA2 values cited above with similar parameters obtained by other investigators in several mammalian tissues suggests that there is wide variation among beta adrenergic receptors.


A polypeptide (AP-A) from sea anemone (Anthopleura xanthogrammica) with potent positive inotropic action. Anthopleurin-A (AP-A), a polypeptide with MW ca. 5500 (53 amino acids), isolated from the sea anemone, Anthopleura xanthogrammica (Brandt), elicited a potent positive inotropic effect but without an accompanying chronotropic effect on the isolated cardiac muscles of rat, rabbit, guinea pig and cat. Similarly in dogs and cats in situ, i.p. injections of AP-A increased the contractile force without effect on heart rate or blood pressure. The cardiotonic potency for AP-A was equivalent to that of isoproterenol but much greater than that for ouabain or glucagon on the isolated cardiac muscle. AP-A increased the contractile force (cardiac output) and decreased atrial pressure in dog heart during pentobarbital-induced failure. This inotropic effect was not inhibited by propranolol pretreatment. The Ca++ requirement to restore the contractile force was less in AP-A-treated than in ouabain or isoproterenol-treated tissues. After AP-A treatment, the cardiac contractility was more resistant to hypoxia and to low or high temperature stress than ouabain-treated or control preparations. AP-A at 5 10(-9) M increased the duration of the action potential, its mean rate of rise and conduction in the guinea-pig atria and ventricles. At the maximum effective concentration, AP-A did not inhibit Na+, K+-activated adenosine triphosphatase, phosphodiesterase (high Km and low Km) and cyclic 3',5'-adenosine monophosphate content of guinea-pig heart. AP-A (5 X 10(-8) to 5 X 10(-7) M) neither contracted nor relaxed the isolated vascular smooth muscle. The results suggest that AP-A may be useful in the clinical management of cardiac failure and as an experimental tool to study the pharmacology and physiology of cardiac muscle.


Isoproterenol antagonism of cardioselective beta adrenergic receptor blocking agents: a comparative study of human and guinea-pig cardiac and bronchial beta adrenergic receptors. pA2 values against isoproterenol were determined for a number of cardioselective and noncardioselective beta adrenergic receptor blocking agents using human and guinea-pig isolated atrial and bronchial or tracheal preparations to study possible species differences. No significant differences in pA2 values for propranolol, pindolol, Ro 3-4787, acebutolol, atenolol, practolol, metoprolol, H 87/07 and tolamolol on bronchial or tracheal beta adrenergic receptors of both species were found. With respect to atrial beta adrenergic receptors, significantly lower pA2 values for human preparations, as compared to guinea-pig preparations, were found for tolamolol and CI 775. These are the only two agents in the series that derive their cardioselectivities from specific nitrogen substitutents. The different potencies of only these two compounds in antagonizing isoproterenol on atrial beta adrenergic receptors of both species suggest a difference in an accessory receptor area close to the site that interacts with the nitrogen atom of beta adrenergic agents.


Interactions between narcotic analgesics and benzodiazepine derivatives on behavior in the mouse. Interactions between the benzodiazepine derivatives, diazepam and oxazepam, and the narcotic analgesics, morphine and methadone, were evaluated on locomotor activity and in the tail-flick and hot-plate tests for analgesia in the mouse. The dose-related stimulation of locomotor activity by morphine was reduced by diazepam and oxazepam at doses which alone had no effect on locomotor activity. However, only oxazepam reduced the dose-related stimulation of locomotor activity by methadone. The observed decreases produced by diazepam and oxazepam were comparable in magnitude to those produced by naloxone. Stimulation of locomotor activity by d-amphetamine was not affected by either diazepam or oxazepam. Dose-response curves for locomotor activity were also determined with morphine and methadone administered intraventricularly. As before, diazepam and naloxone given i.p. decreased the stimulation of locomotor activity produced by morphine, but only naloxone affected methadone-stimulated locomotor activity. Neither diazepam, oxazepam nor naloxone reduced the brain or plasma levels of 3H-morphine or 3H-methadone. In contrast to the results on locomotor activity, neither of these benzodiazepines significantly modified the dose-response curves of morphine or methadone in either test for analgesia. The mechanisms involved in the observed interactions on locomotor activity may be related to the influences of benzodiazepines and narcotic analgesics on motor efferent pathways summating in such a manner as to interfere with the ability of the mice to locomote. The present results demonstrate that prominent interactions occur between members of the  benzodiazepine and narcotic analgesic classes; these interactions are dependent upon both the specific combination of drugs administered and upon the test procedure.


Precipitation of abstinence-like syndrome in morphine-dependent mice by pargyline. In mice rendered morphine-dependent by pellet implantation for 3 days, the administration of pargyline 6 hours after pellet removal intensified narcotic abstinence behavior, particularly the narcotic withdrawal jumping response. Pargyline, 75 mg/kg i.p., caused a 6- to 9-fold increase in the incidence of jumping in mice withdrawing from morphine 6 hours after removal of the pellet, whereas this effect was not observed: 1) 1 hour after the injection of pargyline or 2) in animals still implanted with the morphine pellet. The median effective dose (ED50) of pargyline required to elicit withdrawal jumping in mice implanted with morphine decreased with increasing physical dependence. The ED50 for 72 hours was about one-sixth that after 24 hours of implantation. Additionally, pargyline potentiated naloxone-precipitated withdrawal jumping as evidenced by a reduction of the naloxone ED50 by approximately one-half. Administration of other monoamine oxidase inhibitors such as pheniprazine, iproiazid or tranylcypromine failed to alter the indicence of jumping in dependent mice undergoind abrupt morphine with drawal. Further, dopamine receptor stimulation by amphetamine, pheniprazine or amantadine antagonized the pargyline-induced jumping response. These data suggest that the increased incidence of withdrawal jumping observed after pargyline in morphine-dependent mice is not related to monoamine oxidase inhibition but rather to a possible pargyline-induced decrease in dopaminergic activity.


Effect of sodium para-aminosalicylate on oxygen affinity in normal, sickle and fetal human blood. Sodium para-aminosalicylate (sodium salt of 2-hydroxy-4-aminobenzoic acid, Na-PAS) lowers the oxygen affinity of normal adult human placental, heterozygous and homozygous sickle cell anemic whole blood at 37 degrees C. The reduction of oxygen affinity is related to the type of hemoglobin in the blood. The mean P50 +/- S.E. at pH 7.40 for normal, placental, heterozygoud and homozygous sickle cell anemic blood in 26.2 +/- 0.1, 20.8 +/- 0.3, 26.8 +/- 0.3 and 31.0 +/- 0.5 mm Hg; in the presence of 5.7 mmol of Na-PAS per liter of blood the P50 values are increased to 28.0 +/- 0.3, 22.9 +/- 0.8, 30.5 +/- 0.6 and 33.9 +/- 0.3 mm Hg, respectively. The Bohr effect in normal and placental blood at this Na-PAS concentration is essentially unchanged: in heterozygous and homozygous sickle cell anemic blood, the Bohr factor (deta log P50/deta pH) is reduced from -0.48 +/- 0.02 to -0.41 +/- 0.01 and from -0.53 +/- 0.03 to -0.48 +/- 0.01. The Hill constants (n) of normal and placental blood are not affected by Na-PAS. In homozygous and heterozygous sickle blood, high concentrations of Na-PAS (22.9 mmol/l) decrease the Hill constant from 2.55 to 2.35 and from 2.56 to 2.28, respectively. Na-PAS is more firmly bound to red blood cells than to plasma. The binding of Na-PAS is probably primarily ionic in nature since the drug can be almost completely removed from blood components by dialysis. The changes in oxygen affinity caused by Na-PAS are consistent with conformational changes (R leads to T) which enhance the presence of deoxyhemoglobin.


Drug blockade of open end-plate channels. 1. The actions of amylobarbitone, thiopentone, methohexitone and methyprylone at voltage-clamped frog end-plates were studied. 2. In the presence of barbiturates the conductance change evoked by an iontophoretic carbachol application was reduced by a prepulse of carbachol. The extra inhibition evoked by a prepulse disappeared exponentially with a time constant of 150-200 ms. 3. Barbiturates produce an increased rate of decay of nerve evoked endplate currents. Tne concentration and voltage dependence of the barbtiruate e.p.c. decay rates tally with the hypothesis that the increased rate of decay is due to block of active receptor-channel complexes by barbiturates with a rate constant of  10(6) M-1S-1. 4. Conductance changes produced by bath applied agonists were depressed by thiopentone, the effect becoming greater the higher the agonist concentration. This effect, and also the observation that the concentration of thiopentone required to depress the bath agonist response is much greater than the apparent dissociation constant for binding to active receptor-channel complexes calculated from kinetic measurements, suggest that the selectivity for binding to open receptor-channel complexes is very high. 5. Methyprylone, which is structurally similar to the barbiturates, is only a weak antagonist and shows no interpulse interaction. It was predicted that methyprylone should produce fast and slow components in the e.p.c. decay, and this prediction was verified. 6. In the presence of barbiturates large iontophoretic carbachol applications produce conductance changes which show fast and slow components. Under these conditions the effects of carbachol prepulses become complex. However the effects are qualitatively consistent with the notion that different components of the response are contributed by channels located at various distances from the iontophoretic pipette tip. 7. All the data agree with a model in which the channel has three stages: closed, open and blocked. Only open channels can block, and blocked channels can only open.


Conductances, diffusion and streaming potentials in the rat proximal tubule. 1. Transtubular potential differences and specific resistances were measured in rat proximal tubules by means of single and double barrelled glass micro-electrodes. 2. Tip localization was made by observation of effective resistance changes measured with double barrelled micro-electrodes upon passage of oil droplets, and by perfusion with choline C1. 3. Mean early proximal p.d.s. of the order of -1 to -2 mV,  and late values of +0-5 to +1mV were found. Mean specific resistances ranged from 12 to 15 omega cm2. 4. Diffusion potentials and single ion relative conductances were evaluated, perfusing the lumen with solutions differing only with respect to one salt concentration. Na and K conductances were similar and greater than those of C1. 5. Luminal and peritubular perfusions with hypotonic solutions showed the occurrence of streaming potentials in this structure suggesting the existence of pores lined with negative charges. The effective diameter of these pores appeared to be reduced by hypotonic perfusion, as evidenced by a significant increase in resistance, indicating that the main ion path across this structure is represented by intercellular spaces.


Some aspects of foetal and uteroplacental metabolism in cows with indwelling umbilical and uterine vascular catheters. 1. The experiments were carried out on conscious pregnant Jersey cows with intravascular catheters implanted during late gestation in umbilical and uterine vessels. All but three of fifteen animals delivered live healthy calves. 2. Rountine daily analyses were made of blood gas tensions, pH and packed cell volume in foetal and maternal blood; plasma concentrations of glucose, fructose, lactate and urea were also determined. Measurements of plasma free fatty acids and blood acetate concentrations were made less frequently. Foetal heart rate and arterial blood pressure were recorded in animals with an umbilical arterial catheter. 3. The concentration differences between foetal and maternal blood or plasma in glucose, urea and acetate were measured in fifteen animals. The maternal-to-foetal glucose and acetate gradients across the placenta were high while the foetal-to-maternal plasma urea differences were small. 4. In those animals with patent arterial and venous catheters, uterine and umbilical blood flows were measured together with the arteriovenous differences in 02, glucose, acetate and lactate so that rates of foetal and uterine consumption could be estimated. The rates of utilization of O2, glucose and acetate by the foetus were lower than the values for the whole uterus, while the uteroplacental metabolism of these substrates was very high. 5. Significant amounts of lactate, which appeared to be produced by the uteroplacental tissue, were utilized by the foetus; the remainder passed into the uterine venous blood. 6. The total substrate/O2 quotient for the foetus, calculated from the utilization of known metabolites, appeared to be greater than 1. Thus, in the calf some carbon accumulation from sources other than amino acids, the uptake of which was not measured, would seem to occur. These results and the metabolic activity of the uterine tissues are discussed in relation to comparable findings in the sheep.


Stimulation-induced factors which affect augmentation and potentiation of trasmitter release at the neuromuscular junction. 1. End-plate potentials (e.p.p.s) were recorded from frog sartorius neuromuscular junctions under conditions of decreased transmitter release to study the effect of repetitive stimulation on augmentation and potentiation of transmitter release. 2. The magnitudes and time constants of decay of augmentation and potentiation were determined both following a primary conditioning train and following an identical secondary conditioning train applied from 30 to 170 sec after the primary conditioning train. 3. The magnitude of augmentation following the secondary conditioning trains was increased over that following the primary conditioning trains even though augmentation, with a time constant of decay of about 7 sec, had decayed to insignificant levels before the onset of the secondary trains. This increase in augmentation was not due to a change in its rate of decay during the secondary trains. 4. The increased magnitude of augmentation can be described as arising from an expression factor which, for conditioning trains of 200 impulses at 20/sec, has an initial magnitude of 1-6 +/- 1-2 (S.D. of observation) (the magnitude of augmentation is increased 2-6 times) and decays approximately exponentially with a time constant of 90 +/- 50 (S.D. of observation) sec. The expression factor thus decays about ten times slower than augmentation. 5. Doubling the number of impulses in the primary conditioning train from 100 to 200 led to a 2-8 +/- 1-0 (S.D. of observation) times increase in the magnitude of the expression factor, estimated by placing a 200 impulse secondary conditioning train 40 sec after the primary conditioning train. 6. The expression factor, while increasing the magnitude of augmentation, had little or no effect on the magnitude of potentiation or on trasmitter release in the absence of augmentation. The expression factor decayed about twice as slowly as potentiation. 7. The time constants characterizing the decay of potentiation were greater following the secondary conditioning trains than following the primary conditioning trains. 8. The increased time constant for the decay of potentiation can be described as arising from a time constant factor which, for conditioning trains of 200 impulses at 20/sec, has an initial magnitude of 1-2 +/- 0-7 (S.D. of observation) (the time constant of potentiation is increased 2-2 times) and decays approximately exponentially with a time constant of 130 +/- 45 (S.D. of observation) sec. The time constant factor decayed about three times slower than potentiation. 9. Doubling the number of impulses in the primary conditioning train from 100 to 200 led to a 1-6 +/- 0-8 (S.D. of observation) times increase in the magnitude of the time constant factor, estimated by placing a 200 impulse secondary conditioning train 40 sec after the primary conditioning train. 10...


Gastric emptying of organic acids in the dog. Test meals of 300 ml. of six different organic acids were instilled into the stomach of six healthy mongrel dogs. Citric, acetic, propionic, lactic, tartaric and succinic acid were given in 50, 100, 150, and 200 mN concentrations. 2. During the emptying process, the gastric contents were aspirated and immediately re-instilled at 10 min intervals, and the following parameters were recorded: volume, concentration of the organic anion, pH, hydrogen ion concentration and osmolarity. 3. By multiple stepwise regression analysis, the combination of parameters which most effectively determines gastric emptying rate was found to be: concentration of the organic anion, followed by intragastric volume and number of previous test meals given on the same day. These three parameters appear in the equation for gastric emptying rate in which the individual characteristic of each acid is expressed by a constant. 4. Among the various acids, inhibition of emptying rate increases with rising number of carboxylic groups of the acid and its molecular weight. 5. After proximal gastric vagotomy, emptying rate of organic acids is independent of volume, and emptying approaches an exponential pattern. 6. A model for gastric emptying of organic acids with at least three different receptors is proposed: one for the structure of the organic acid, one for concentration and one for intragastric volume.


Evaluation of analgesic action and efficacy of antirheumatic drugs. Study of 10 drugs in 684 patients with rheumatoid arthritis. A single-blind non-crossover method for assessing the potential effectiveness of antirheumatic drugs has been described. The method employs entirely subjective indices and incorporates a daily pain chart for measuring the pain response over the duration of the trial. In addition, the mean number of days withdrawn and patients' satisfaction rating are measured. The statistical method can correct for initial imbalances between groups and allows for the valid comparison of drugs from separate trials. Ten antirheumatic medications were evaluated using this technique in 684 patients with rheumatoid arthritis, and the results are in agreement with those of previous studies using standard clinical methods. The new method is simple, rapid in performance, economical in terms of cost and time, and has been shown to be sensitive and reproducible. The results indicate that there are no significant differences in efficacy between the currently available non-steroidal, anti-inflammatory analgesic drugs, in the treatment of rheumatoid arthritis.


Sympathomimetic amines having a carbostyril nucleus. A series of new sympathomimetic amines containing an 8-hydroxycarbostyril moiety was synthesized. These compounds probably exist as resonance hybrids having two acidic hydrogen atoms in locations approximating to those of the hydroxyl groups of catechol-containing adrenergic agents. In an in vitro test, many of these compounds showed potent activity for relaxation of guinea pig tracheal smooth muscle. One of the compounds was 24 000 times more potent than isoproterenol. Their actions on cardiac muscle were also examined in vitro by measuring increase in the beating rate of the right atria of guinea pigs. Several of the compounds appeared to be beta-selective. Some of the compounds seem suitable for use as bronchodilators. The structure-activity relationships of these compounds were discussed in comparison with those of catecholamines.


Fusion in phospholipid spherical membranes. II. Effect of cholesterol, divalent ions and pH. Effect of cholesterol, divalent ions and pH on spherical bilayer membrane fusion was studied as a function of increasing temperature. Spherical bilayer membranes were composed of natural [phosphatidylcholine (PC) and phosphatidylserine (PS)] as well as synthetic (dipalmitoyl-PC, dimyristoyl-PC and dioleoyl-PC) phospholipids. Incorporation of cholesterol into the membrane (33% by weight) suppressed the fusion temperature and also greatly reduced the percentage of membrane fusion. The presence of 1 mM divalent ions (Ca++, Mg++ or Mn++) on both sides or one side of the PC membrane did not affect appreciably its fusion characteristic with temperature, but the PS membrane fusion with temperature was greatly enhanced by the presence of divalent ions. The variation of pH of the environmental solution in the range of 5.5 approximately 7.0 did not affect the membrane fusion characteristic. However, at pH 8.5, the fusion with respect to temperature was shifted toward the lower temperature by approximately 3degreesC for PC and PS membranes, and at pH 3.0 the opposite situation was observed as the fusion temperature was increased by 6degreesC for PS membranes and by 4degreesC for PC membranes The results seem to indicate that membrane fluidity and structural instability in the bilayer are important for membrane fusion to occur.


Properties of two isolated antigens associated with bovine leukemia virus infection. We isolated an ether-resistant internal antigen and an ether-sensitive antigen previously described in relation to bovine leukemia virus infection. These two antigens have now been isolated by isoelectric focusing and concanavalin A affinity chromatography, respectively. The ether-resistant antigen exhibited isoelectric heterogeneity with a major peak at pH 7.2 and a minor peak at pH 6.2. Its molecular weight, estimated by sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE), was 23,000 (p23), and it gave a sedimentation value of 2.3s. For material containing ether-sensitive antigen, analyzed by SDS-PAGE, protein staining revealed four components with molecular weights of 18,000, 25,000, 45,000, and 55,000. Two of these [45,000 (gp45) and 55,000 (gp55)] were stained by periodic acid-Schiff reagent. Isoelectric point and sedimentation value of the major glycoprotein (gp45) were pH 5.0 and 3.4s, respectively; no immunologic cross-reactivity was found between p23 and glycoprotein antigen.


Glutathione and gamma glutamyl transpeptidase in rat liver during chemical carcinogenesis. Continued administration of several hepatocarcinogens led to an increase in the concentration of glutathione (GSH) in the livers of intact, but not of hypophysectomized or adrenalectomized rats. The concentration of GSH remained high untill the development of hyperplastic nodules. Subsequently, the concentration of GSH dropped to the normal level or below. A single dose of 3'-methyl-4-dimethylaminoazobenzene (3'-Me-DAB) produced an increase of GSH which, within a certain range, depended upon the amount of the carcinogen. In well differentiated, slowly growing hepatomas, the concentration of GSH approached the level in normal adult rat liver. On the other hand, in nondifferentiated and rapidly growing hepatomas, GSH was only 30-40% of that in normal liver. The activity of gamma-glutamyl transpeptidase (GTase) increased within 24-48 hours after a single large dose of 3'-Me-DAB. Continued feeding of 3'-Me-DAB led to an exponential increase of GTase. During hepatocarcinogenesis, the level of GTase activity corresponded to the degree and size of pathologic changes produced in rat liver. Chloramphenicol partially inhibited the increase of GTase induced by 2-acetylaminofluorene. Pretreatment with 3-methylcholanthrene partially inhibited the increase of GTase that had been induced by a single dose of 3'-Me-DAB. Puromycin partially inhibited the increase of GTase induced by several doses of dimethylnitrosamine. These observations indicated a close connection between the activation of GTase and chemical carcinogenesis in rat liver. Measurements of GTase activity in 12 Morris hepatomas supported this conclusion; their GTase levels were greatly elevated compared with that in normal adult rat liver.


Cyclic nucleotides in the regulation of expression of differentiated functions in neuroblastoma cells. Adenosine 3',5'-cyclic monophosphate (cAMP) may be one of the important factors in regulating the expression of many differentiated functions in neuroblastoma cells, but some of these functions can be induced by agents that do not increase the intracellular level of cAMP. An elevation of the intracellular level of guanosine 3',5'-cyclic monophosphate (cGMP) neither induced differentiation nor antagonized the effects of cAMP. Neuroblastoma cells increased the level of cAMP-binding proteins during differentiation, whereas glial cells and L-cells did not. This might have accounted in part for an increase in the intracellular level of cAMP even in the presence of high phosphodiesterase activity in neuroblastoma cells, since the protein-bound with the same proteins, but cAMP had about 10 times higher affinity than did cGMP. cAMP promoted the organization of microtubules and microfilaments necessary for the expression of differentiated phenotypes. The extension of neurites required the synthesis of new protein, but it did not need the synthesis of new RNA. cAMP induced differentiation in neuroblastoma cells by increasing the expression of some genetic information while suppressing the expression of others; e.g., the activities of neural enzymes increased, whereas the synthesis of histone and the phosphorylation of H1-histone markedly decreased in differentiated cells. A hypothesis was offered: An increase in cAMP phosphodiesterase activity as a result of mutation in the regulatory gene for phosphodiesterase in a single, or group of, dividing nerve cell(s) is the primary lesion that leads to malignancy. Based on the concept that selective cytocytoxic drugs should be used with agents that cause differentiation, a new therapeutic approach was suggested for the treatment of neuroblastoma. This involved administration of sodium butyrate followed by L-DOPA or prostaglandin E1 in the presence of cAMP phosphodiesterase inhibitor followed by the less immunosuppressive vincristine and 5-(3,3-dimethyl-1-triazeno)imidazole-4-carboxamide.


Catecholamine metabolism in neuroblastoma. Previous studies indicating the importance of catecholamine metabolism in neuroblastoma were briefly reviewed. Metabolic pathways were presented showing how the major urinary metabolites 3-methoxy-4-hydroxymandelic acid (VMA) and 3-methoxy-4-hydroxy-phenylacetic acid (HVA) are formed from norepinephrine and from dopamine plus 3,4-dihydroxyphenylalanine (DOPA), respectively. For 289 neuroblastoma patients at the time of diagnosis, the urinary excretion of VMA was significantly elevated in 75%, and HVA was elevated in 80%. Periodic assay of these metabolites during the course of the disease revealed that the excretion trends were of prognostic value with 80-90% reliability. By contrast, when the excretion in only the initial urine specimens was considered, the survival rate was the same for patients with normal, and with significantly elevated, excretion. Review of the results of tracer studies aimed at elucidating the in vivo metabolic origins of the urinary metabolites suggested that a) in neuroblastoma, the catecholamines were largely inactivated by intracellular metabolism in the tumor cells; b) there was excess production and excretion of the norepinephrine precursors, DOPA and dopamine; and c) in the tumors of most neuroblastoma patients, the initial enzyme in catecholamine synthesis, tyrosine hydroxylase, had an activity comparable with that in normal adrenal glands. The importance of the metabolism of catecholamines in patients with neuroblastoma was stressed: a) The excretion of elevated levels of urinary catecholamine metabolites were useful in diagnosis and in following the course of the disease, and b) study of the catecholamine metabolism in these patients permitted examination of possible relationships between the activity of the enzymes involved in catecholamine synthesis and the malignancy of this tumor.


Exonuclease associated with bacteriophage T5-Induced DNA polymerase. T-5-induced DNA polymerase has been shown to possess a 3' leads to 5'-exonucleolytic activity. The exonuclease acts on both native and denatured DNA, but the apparent rate of degradation of denatured DNA is about five times faster than that for native DNA. The enzyme appears to act only on 3'-OH ends and produces mainly 5'-dNMP's. Like polymerase activity, exonuclease activity shows a pH optimum around 8.6. Mg2+, dithiothreitol, and N-ethylmaleimide had identical effects on both the activities. Nicked DNA was almost totally protected from exonuclease action under synthetic conditions, i.e., in the presence of 4dNTP's. Denatured DNA was partly degraded in the early phase of incubation with 4dNTP's, presumably due to unhybridized tails at the 3'-OH primer ends. However, the exonuclease activity was operative in both cases under synthetic conditions, as evidenced by template-dependent conversion of [3H]dTTP to [3H]dTMP.


Structural proteins of polyoma virus: proteolytic degradation of virion proteins by exogenous and by virion-associated proteases. A model has previously been proposed for the genetic relatedness of the structural proteins of polyoma virus, based upon similarities in the peptide maps of the major capsid protein VP1 with the virion proteins VP2 and VP3. Newer evidence suggests that this model is incorrect, and that protein VP1 is a product of one viral gene and that the multiple components of VP2 and VP3 are products of a second viral gene. Two-dimensional peptide maps of several preparations of polyoma purified separately from four separate infected-cell lysates has shown a variable content of VP1 peptides in proteins VP2 and VP3, with some preparations being free of detectable VP1 material in VP2 and VP3. An alternative explanation for the presence of VP1 peptides in the regions of VP2 and VP3 of some polyoma preparations involves the cleavage of proteins of polyoma virions during exposure to proteolytic enzymes in lysates of infected cells or to endogenous proteolytic activity of virions. Prolonged incubation of infected-cell lysates at 37 degrees C leads to an increase in the amount of 86,000-dalton dimer of VP1, a decrease in the relative amount of VP1, a decrease in or a loss of the lower band of VP2, and the appearance of a new major protein band of approximately 29,000 daltons. Two-dimensional peptide maps of the new 29,000-dalton protein show that it contains some VP1 peptides, indicating that this protein is derived from proteolytic cleavage of VP1. In addition, extensively purified polyoma virus contains a proteolytic activity that can be activated during disruption of the virus with 0.2 M Na2CO3-NaHCO3 (pH 10.6) in the presence of 5 X 10(-3) M dithiothreitol.


Purification and properties of glucose-6-phosphate dehydrogenase from Bacillus subtilis spores. Glucose-6-phosphate dehydrogenase [D-glucose-6-phosphate: NADP oxidoreductase, EC. 1. 1. 1. 49] obtained from spores of Bacillus subtilis PCI 219 strain was partially purified by filtration on Sephadex G-200, ammonium sulfate fractionation and chromatography on DEAE-Sephadex A-25 (about 54-fold). The optimum pH for stability of this enzyme was about 6.3 and the optimum pH for the reaction about 8.3. The apparent Km values of the enzyme were 5.7 X 10(-4) M for glucose-6-phosphate and 2.4 X 10(-4) M for nicotinamide adenine dinucleotide phosphate (NADP). The isoelectric point was about pH 3.9. The enzyme activity was unaffected by the addition of Mg++ or Ca++. The inactive glucose-6-phosphate dehydrogenase obtained from the spores heated at 85 C for 30 min was not reactivated by the addition of ethylenediaminetetraacetic acid, dipicolinic acid or some salts unlike inactive glucose dehydrogenase.


A new analgesic testing method using ultrasonic stimulation. I. Effects of narcotic and nonnarcotic analgesics. A quantitative method for measuring pain threshold by the use of ultrasonic stimulation in mice has been designed. The method had the advantage of precision, simplicity of technique, rapidity of measurement, and the fact that the stimuli is innocuous upon repeated application. The nature of the senstaions induced by ultrasonic stimulus is somewhat like that felt with a prick type of pain. Pentazocine (30, 100, 150 mg/kg i.p.) aminopyrine (15,50, 100, 150 mg/kg i.p.), phenacetin (100,150, 200, 250 mg/kg i.p.) sodium salicylate (150, 200, 250 mg/kg i.p.) and other antipyretic analgesics were active in a wide range of doses indicating that this technique is sensitive to the narcotic antagonist and to the weak analgesics as well as to the narcotic analgesics as well as to the narcotic analgesics such as morphine (2.5, 5, 10, 15 mg/kg i.p.), codeine (10, 20, 25, 30, 50 mg/kg i.p.) and pethidine (5,10, 15, 20, 25 mg/kg i.p.). The ultrasonic method is, therefore, applicable in screening procedures when attempting to evaluate the analgesic potency of a wide variety of chemical agents.


Studies on the mode of antagonism between adrenergic beta-mimetics and beta-blocking agents (III). Functional antagonism between beta-mimetics and spasmogens. New equations which can explain the following characteristic phenomena in the functional antagonism between isoproterenol (ISO) and spasmogens in guinea-pig trachea are proposed: (1) The amplitude of relaxation of the muscle induced by ISO varied depending on the concentration of a spasmogen used (histamine or carbachol). (2) The dose-response curves for the relaxation by ISO shifted to the right in a parallel manner as the concentration of the spasmogen increased, and became stationary at high concentrations of the spasmogen. (3) The slope of the dose-response curve became steeper with increasing concentrations of the spasmogen. When the saturable uptake process of ISO was taken into consideration, a satisfactory parallel was seen between the theoretical dose-response curves and the present experimental results.


Studies on the mode of antagonism between adrenergic beta-mimetics and beta-blocking agents (IV). Influence of functional antagonism by spasmogens. A new theory is presented to describe the effect of functional antagonism on the competitive antagonism between adrenergic beta-mimetics and beta-blockers. According to this theory the shape of the log (dose ratio-1) vs.--log [B] curve and the apparent pA2 value in competitive antagonism should be affected by functional antagonism when the agonist is taken up by the saturable uptake process, and this was experimentally confirmed. The competitive antagonism between isoproterenol (ISO) and propranolol (Prop) was influenced by the functional antagonism between ISO and spasmogens (histamine and carbachol). The log (dose ratio-1) vs. --log [B] curve is ISO-Prop competitive antagonism was shifted variously depending on the concentration of a spasmogen used. Theoretical predictions and experimental results were in good parallel.


HLA antigens in arterial occlusive diseases in Japan. Using a NIH standard lymphocytotoxicity test, a possible Japanese specific HLA antigen, HLA-BJW 22.2 was identified in 17 out of 48 patients with thromboangiitis obliterans (35.4 per cent), in 5 out of 15 patients with Takayasu's arteritis (33.3 per cent) and in 11 out of 113 normal controls (9.7 per cent). On the other hand, HLA-CWl was found in 4 out of 47 patients with arteriosclerosis obliterans (8.5 per cent) and in 41 out of 113 normal controls (36.3 per cent).


[Comparative evaluation of the clinical action of a series of beta-adrenergic blockaders]. A comparative clinical study of the efficacy of Benzoral, Trasicor, Viskene, Aptene, Eraldine and Inderal was conducted in the ischaemic heart disease patients. Their antiarrhythmic and antianginal effect was determined, as well as their optimum therapeutic dosages, the activity of their specific beta-adrenolytic properties, the effect of the drugs on the bronchi and the peripheral venous tone. Apart from the clinical study, electro- and polycardiography, functional pulmonary tests and the Schellong orthostatic test were used. All the drugs in question were found to produce a distinct specific beta-blocking effect. They are effective in cases of atrial and ventricular extrasystole, paroxysmal tachycardia, sinus tachycardia and tachyarrhythmic fibrillation, as well as for the prevention of anginal attacks and arrhythmic fibrillation. All the drugs produce a negative inotropic effect, Inderal--the strongest, Viskene and Benzoral--the weakest. All beta-blockers can impair bronchial patency in patients with bronchial obstruction. This effect is least pronounced with Eraldine that may be used as the drug of choice in such cases. In most cases the beta-blockers do not affect the peripheral venous tone, but in some cases they may reduce it.


[Change in the central and regional (brain) hemodynamics in the treatment of hypertension using beta-adrenergic blockaders]. The haemodynamic parameters were studied dynamically by way of noninvasive techniques--tetrapolar thoracic rheography in the course of treatment of 48 patients with essential hypertension Stage IB and IIA urth beta-blocking agents Obsidan and Visken. It was found that as early as by the 5th day of therapy the stroke volume and heart rate decreased, the maximum fall being noted after 2-3 weeks of treatment. The reflex elevation of the total peripheral resistance was moderate, as a result of which a gradual reduction of the arterial pressure developed. The state of the cerebral circulation significantly improved in the course of the treatment (as shown by rheoencephalography) and the tone of the cerebral arteries decreased. After 2-3 weeks of beta-blockers therapy favourable shifts were observed in the response of the general and cerebral haemodynamics to the orthostatic test.


[Assay of carbromal and its main metabolite (2-ethyl-butyryl-urea) in biological fluids (author's transl)]. The materials mentioned above are reextracted from an ether solution by 2 N sodium hydroxide. The UV extinction of the aqueous layer at 232 nm and 30 degrees C is followed by means of a slave recorder. The original extinction is found by back-extrapolating to the time of re-extraction. It has to be corrected for the "biological matrix" by subtracting the extinction value after complete hydrolysis. Most interfering substances in the ether solution (carboxylic acids, barbiturates) may be removed previously by washing with aqueous buffers (pH 7.0 and 10.5).


Histamine H2-receptor antagonists and gastric acid secretion -- a progress report. Histamine H2-receptor antagonists, including burimamide, metiamide and cimetidine, are effective antagonists of histamine-stimulated acid secretion from mammalian, avian or reptilian gastric mucosa. Acid secretion stimulated by gastrin or pentagastrin is also inhibited by these drugs, but there is disagreement about the effects of these drugs on acid secretion resulting from activation of acetylcholine receptors. Based on the pharmacological evidence possibilities of treatment by these drugs were discussed in cases with excessive stimulation of acid secretion due to high blood levels of histamine or gastrin. The positive results in several trials on Zollinger-Ellison syndrome and peptic ulcer were very impressive. Some practical problems have still to be solved, for example the appropriate phase for applying the drugs. The demonstrated clinical effectiveness, however, against peptic ulceration offers a clear alternative to surgery for many patients.


[Selection of a urine preservative agent in relation to oxidative-catalytic methods of water regeneration]. Various chemicals were assayed as possible urine conservers to the used in space water reclamation systems. With respect to the antimicrobial activity and the quality of reclaimed water formalin at a concentration of 0.1% was selected as the best conserver. The reagent ensures urine preservation for 3 months.


[Hypoxia and polytrauma].

[Hypoxia and polytrauma]. The importance of polytrauma and hypoxia, resp., is discussed by the authors with regard to the mortality and the common effect of these is analysed. It was found that in the mortality of the patients suffered polytraumatism the first place (59,4%) is taken by such lesions, in which simultaneous lesion of the skull and the thorax occurs. The values of the blood gas and the acid-base balance of the patients who had suffered polytraumatism, were examined in the 12th--24th hours proceding the death. It was found that whereas--using the possibilities of the intensive therapy--the values of pH, paCO2 and BE could be kept in a part of the cases between the physiological limits--the paO2 value was under the normal value in all cases--moreover 2/3 of the values fell into the domain between 40--60 mmHg--signifying severe hypoxia. On the basis of the analysis it may be presumed that in the process leading to death of the patients who had suffered polytraumatism the anoxic hypoxy plays considerable role. This is supported also by the earlier data published by the institute, according to which the mortality in itself high--33.8%--of polytraumatism increases to 71.4%, if it is associated hypoxy. Consequently the aim of the therapy must be to exert the greatest activity in order to prevent or to combat, resp., the anoxic hypoxy.