Defective phagocyte adherence in acute poststreptococcal glomerulonephritis: clinical and laboratory observations. The adherence of circulating phagocytes to glass was studied in 15 children with acute poststreptococcal glomerulonephritis and in 27 healthy adults, 21 healthy children, and 14 children with normocomplementemic renal disease. The phagocytic adherence to glass in the patients with hypocomplementemic PSGN differed significantly from that of the control groups (p=less than 0.001). There was a positive correlation of phagocyte adherence with plasma C3 but not with plasma C4, C3, properdin factor B, severity of illness, or drugs administered. In addition, the adherence defect was present in two normocomplementemic PSGN patients. The defect gradually resolved in all patients with clinical improvement: it was useful as an index of recovery. The in vitro addition of functional C3 to whole blood produced the adherence defect in normal subjects and failed to correct the defect in patients with PSGN. It was postulated that a fragment of activated complement may have blocked a membrane receptor on these phagocytes and interfered with their adherence to glass.


Hyperphenylalaninemia due to dihydropteridine reductase deficiency. Assay of the enzyme in fibroblasts from affected infants, heterozygotes, and in normal amniotic fluid cells. Two infant siblings with modest elevations of serum phenylalanine concentrations had seizures and developmental regression: they died in their second year. Dihydropteridine reductase activity, which can be measured in normal cultured skin fibroblasts, was measured in the younger sibling and was absent. Parents of the two siblings and parents of a previously reported patient all showed 50% or less of the normal dihydropteridine reductase activity in their cultured fibroblasts. Dihydropteridine reductase activity is also present in normal cultured amniotic fluid cells, offering the possibility of prenatal diagnosis. Absence of dihydropteridine reductase results not only in a defect in the conversion of phenylalaning to tyrosine, but also in the biosynthesis of the neurotransmitters, dopamine, norephinephrine, and serotonin. Since deficiencies in these neurotransmitters would not be alleviated by a phenylalanine-restricted diet, it is important to establish the nature of the enzymatic defect in all suspected variants of phenylketonuria.


Enterovirus infections in neonates.

Enterovirus infections in neonates. Twenty-seven ill neonates with enterovirus infections were studied to learn if enterovirus infection can be distinguished from neonatal sepsis. Enterovirus infection was associated with the summer-fall season (93%), recent maternal illness (59%), absence of other perinatal problems (81%), and findings of fever (93%), viral meningitis (62%), diarrhea (81%), and rash (41%). Four children developed thrombocytopenia and three necrotizing enterocolitis. Three children died, all with Coxsackie B virus infections that likely were acquired in utero. Although no single feature is pathognomonic, this constellation of epidemiologic and clinical findings, coupled with negative bacterial cultures, should suggest the possibility of neonatal enterovirus infection.


Hypertension in infants--a complication of umbilical arterial catheterization. Hypertension was observed in ten infants. Seven had thrombosis either of one renal artery or of both. The seven infants had previously had an indwelling catheter in the umbilical artery. One infant who had not had an indwelling umbilical arterial catheter had stenosis of a renal artery. No etiology for the hypertension was found in two infants, one of whom had had an umbilical arterial catheter. Response to antihypertensive medication was generally poor. Five of the infants died. We recommend prompt diagnostic evaluation in hypertensive infants. Nephrectomy should be considered, if the renal artery is occluded. Hypertension appears to be a life-threatening complication of umbilical arterial catheterization.


Relationships between maternal glucose intolerance and neonatal blood glucose. Blood glucose changes in 63 infants during the first three hours of life were related to indices of glucose tolerance of their mothers. Of the mothers, 34 had insulin-dependent diabetes, 16 had gestational diabetes, and 11 had minor abnormalities of glucose tolerance. The fasting blood glucose level of the mother and the umbilical cord blood glucose level were both proportional to the rate of glucose decline in the infant after birth which, in turn, was inversely related to the lowest glucose level attained within three hours. Hypoglycemia occurred in 77% of the infants of diabetic mothers, 25% of the infants of mothers with gestational diabetes, and one of 12 (8%) of infants of mothers with minor degrees of glucose intolerance. The blood glucose level at two hours during an oral glucose tolerance test in the mother can be used to predict the probability of her infant having neonatal hypoglycemia.


Growth graphs for the clinical assessment of infants of varying gestational age. Two graphs are presented showing means and 1 and 2 SD for growth in weight, length, and head circumference: (1) a fetal-infant graph with lines of growth from 26 weeks of gestational age until one year of age after ""term'' has been reached: and (2) a similarly constructed graph for children ages one through ten years. The standards of growth were obtained from published data in which the subjects received optimal health care. The graphs allow comparisons of infants of varying gestational age with standards for that age. Normal and abnormal deviations in growth are easily identified. Some examples of common variations in physical growth are described.


Reversible oxacillin hepatotoxicity.

Reversible oxacillin hepatotoxicity. Eight patients developed elevations of hepatic enzymes while receiving oxacillin intravenously. In all instances the patients were asymptomatic and anicteric. Peripheral eosinophilia was present in five of eight patients. In each patient change of therapy to a different pencillinase-resistant penicillin or to penicillin G was associated with a rapid decrease in liver function abnormalities and evenutal return of the enzymatic values to normal. Change of medication to an alternative penicillinase-resistant penicillin or to penicillin G is suggested as a safe procedure for completion of antistaphylococcal therapy in patient who develop oxacillin-related hepatotoxicity.


Behavioural concomitants of prenatal addiction to narcotics. Behavioral characteristics of infants of methadone-treated and nonaddicted women were studied during the neonatal period and at three, six, and 12 months of age. Several Brazelton Neonatal Behavioral Assment Scale measures differentiated between groups. Major differences occurred in irritability of the central nervous system, and these measures appeared able to predict severity of withdrawal. The increased tremulousness of addicted infants remained through at least the first month of life. Mental and motor development was within normal limits in both groups throughout the year. However, the addicted infants showed a progressive decline in psychomotor performance whereas nonaddicted infants' scores remained stable.


Mothers as volunteers in an oncology clinic. Mothers of children who had died of cancer were successfully utilized as volunteers in a pediatric oncology clinic to provide emotional support and practical assistance to other children afflicted with the same disease and to their families. At the start of the program these volunteers were carefully interviewed to determine their willingness and their emotional ability to participate on a consistent basis. Following an eight-week training program with a psychiatrist, a social worker, and a nurse, they began working in a large pediatric oncology clinic one day a week. Over an 18-month period they have become valuable members of the oncology team by helping to improve communications, to alleviate frustrations, and in giving additional emotional support to the children and their families.


Partial purification of amastigotes from cutaneous lesions of American leishmaniasis. Amastigotes of Leishmania mexicana, L. mexicana amazonensis, L. brasiliensis, and L. enriettii were isolated from lesions in infected animals. Numbers of amastigotes recovered ranged from 1 X 10(7) to 7 X 10(8), depending on the strain of leishmania. Trypsinization disassociated the lesions and released the parasites. After 18 to 24 hr incubation at 37 C in tissue culture media with antibiotics, many of the intact host cells attached to the flask. Amastigotes were collected from the media in relatively pure preparations. Electron microscopy revealed no morphological alterations of the amastigotes and minimal contamination by membranes and cell fragments.


The genus Myxidium (Protozoa: Myxosporida) in macrourid fishes. Five species, 3 new, of myoxosporida in the genus Myxidium were recovered from 7 genera and 23 species of deepsea macrourids. Although some Myxidium species were geographically dispersed they showed remarkable spore size stability. Two forms, "long" and "stubby" are described for M. coryphaenoidium. Abnormal M. coryphaenoidium spores are shown to resemble superficially other species and genera.


Myxosporida (Protozoa) in California rockfish, Sebastes spp. Six genera and 15 species, 2 new, of myxosporida were recovered from 14 species of California marine rockfish, Sebastes. The spores of Leptotheca sebasta sp. n. are arched with thick, equal shell valves and large round polar capsules. They are greater in width and sutural diameter and more crescentic than L. latesi. Ceratomyxa sebasta sp. n. is crescentic in shape with equal shell valves. The spores of C. sebasta are shorter in sutural diameter, larger in width, and less crescentic than C. hokarari.


Responses of Megalodiscus temperatus miracidia to amino and sialic acids found in snail-conditioned water. Analysis of snail-conditioned  water (SCW) from Helisoma trivolvis revealed 17 free amino acids. Those in great concentration were glycine, serine, and alanine. The concentration of sialic acid was found to be twice that of the most abundant amino acid. The behavior of miracidia of Megalodiscus temperatus, measured by the contact with return method, to agar cylinders containing single amino acids and sialic acid indicated greater responses to polar molecules charged either positively or negatively at neutral pH. The molecules elicting the greatest response were aspartic, glutamic, and sialic acid. No correlation was found between concentration of amino acids in H. trivolvis SCW and response of M. temperatus miracidia.


The influence of temperature on the infectivity of Fasciola hepatica miracidia to Lymnaea truncatula. Experiments were performed to study the effect of water temperature on the host-finding capacity (snail localization, attachment, and penetration) of Fasciola hepatica miracidia. Specimens of Lymnaea truncatula were exposed to miracidia labeled in vivo with radioselenium, and the radioactivity which subsequently was confined to the snails was taken as a measure of the host-finding capacity of the parasite. The minimum temperature required for host-finding was 5 to 6 C and the optimum temperature was in the range between 15 and 26 C. The lack of host-finding capacity below 5 to 6 C could be reversed experimentally by raising the temperature. A clear inverse relationship was demonstrated between the environnd 24 C the host-finding capacity ceased after 24 to 30, 20  to 24, and 13 to 20 hr, respectively.


A redescription of Crassicutis archosargi, a digenean exhibiting an unusual tegumental attachment. The homalometrine Crassicutis archosargi from the northern Gulf or Mexico is redescribed, and some related digeneans are discussed. Numerous unidentified refractile bodies occurred in the tegument and other tissues of a few specimens of C. archosargi, and an intimate relationship between the parasite and its piscine host resulting from a modified tegument is reported for others. Binding by the described adhesive tegument increases the number of known ways digeneans attach to their hosts. Several specimens also harbored a histozoic myxosporidan in several tissues and a flagellate, Hexamita sp., in their ceca.


Immunocytochemical studies on Schistosoma mansoni. II. Soluble cercarial antigens in cercarial and schistosomules. The localization of soluble, cercarial antigen preparation (CAP) in cercariae and schistosomules of Schistosoma mansoni was performed at the light and electron microscope levels using the unlabeled antibody method. Reaction produce was observed associated with the contents of the pre- and postacetabular glands and with the filamentous coat of mature cercariae. No reaction product was observed associated with the glycoacalyx of schistosomules. However, several schistosomules did retain remnants of their filamentous coats and reaction product was observed associated with those remains. CAP components were also observed in the area surrounding the intrasporocyst cercariae.


The eosinophilic response of the rat to infection with Taenia taeniaeformis. Rats were dosed with eggs of Taenia taeniaeformis and hematologic parameters were measured throughout the course of primary infection. There was no evidence of anemia but differential leukocyte counts revealed distinct and reproducible patterns of white blood cell changes. A lymphocytosis developed at the end of the 1st and 5th weeks postinfection (p.i.). Neutrophil counts peaked 8 days p.i., although at that time there was no marked neutrophilic infiltration of the tissues. Eosinophil counts began to rise during the 2nd week p.i., and reached a peak during the 3rd week, followed by a decline and then another peak during the 5th week p.i. Eosinophilic infiltration of the tissues was remarkable during the period of peripheral eosinophilia. A wide zone of eosinophils surrounded the developing larvae at 22 days p.i. and persisted in some cases for a further 2 weeks. Eosinophils remained in lesser numbers in the connective tissue capsule throughout the infection, often in association with plasma cells. After oral challenge with 1,000 eggs infected rats showed brisk secondary eosinophilic responses 3 to 7 days later but other hematologic parameters were unaffected. Average peripheral eosinophil counts at 3 and 4 days post-challenge were significantly higher than those in unchallenged controls (P less than 0.05 and P less than 0.01, respectively). There was no detectable increase in eosinophilic infiltration of small intestinal tissues in challenged rats. These results are discussed in relation to current understanding of the mechanisms of eosinophil chemotaxis in vitro and the possible causes of local eosinophil accumulation in parasitic infections in vivo.


Antibody-mediated secondary eosinophilic response to Taenia taeniaeformis in the rat. Normal rats were given intravenous doses of either immune serum or immunoglobulin fractions 24 hr before oral challenge with 1,000 eggs of Taenia taeniaeformis. Total eosinophil counts per mm3 were performed for 3 days prior to and 6 days after challenge. Sensitized rats usually showed sharp peaks of eosinophilia 2 to 6 days after this dose. The pattern of the eosinophilic response was similar to that which occurs after challenge of immune infected rats. The differences in peripheral eosinophil levels in passively immunized and normal rats were statistically significant. Immunoglobulin fractions containing protective IgG2alpha were most effective, but a fraction containing reaginic antibody activity also sensitized rats to give secondary eosinophilic responses. The findings are discussed in relation to the probable contribution of antigen-antibody reactions to the production of secondary eosinophilic responses in experimental cysticercosis.


Metabolic indices for evaluating the in vitro maintenance of Hymenolepis diminuta in the presence and absence of various additives. An in vitro maintenance system for H. diminuta was devised by modifying the cultivation procedure of Schiller (1965). In this diphasic maintenance system, tissue culture medium (Triple Eagle's or NCTC-135) was used, in lieu of whole blood, as the 30% supplement to the agar phase. This provides a more defined system suitable for studying the effects of various additives. Morphological criteria were established which aided in assessing the efficacy of media used for the maintenance of 6- and 8-day-old H. diminuta. When successfully maintained, worms exhibited an intact scolex and neck region, undulatory movements along the strobila as well as integumentary and strobilar integrity. A more sensitive method for evaluating the maintenance of 8-day-old worms employed metabolic indices. Wet weight, protein and glycogen levels for 8-day-old H. diminuta served as base-line data allowing estimation of protein and glycogen contents of each worm prior to maintenance. Following maintenance, ratio of final to initial protein and final to initial glycogen levels (metabolic indices). A metabolic index approaching or exceeding unity suggested a reasonably intact metabolism. The addition of sodium taurocholate to the maintenance media appeared beneficial to the worms by prolonging the retention of normal signs. A combination of additives, taurocholate-nucleosides-lipids, improved the maintenance of H. diminuta for periods exceeding 24 hr as determined by observational criteria and metabolic indices. However, addition of a lipid mixture, or a lipid mixture prepared with a low concentration of taurocholate was not beneficial over a 24 hr period. The maintenance system, observational criteria, base-line data and metabolic indices should be useful for future in vitro studies requiring long-term incubation.


The in vitro effects of farnesol and derivatives on Hymenolepis diminuta. Employing an in vitro maintenance system, in which 8-day-old Hymenolepis diminuta survives for 24 hr (Fioravanti and MacInnis, 1976), it was found that farnesol or farnesal supplementation of the medium had no beneficial effects on maintenance and these substances induced necrosis at higher concentrations. Similar experiments utilizing Schiller's (1965) culture system demonstrated that neither farnesol, farnesal, nor farnesyl methyl ether exhibited growth promoting effects and were toxic to the worms at higher concentrations. In addition, neither the 2-cis, 6-trans nor the 2-trans, 6-trans-isomers of farnesol promoted growth in the Schiller system and at higher concentrations resulted in severe necrosis within 24 hr.


Putative neurosecretory cells of the cestode Hymenolepis microstoma. Putative neurosecretory cells were observed with the electron microscope in the nerve cords of the neck region of Hymenolepis microstoma. The cells show evidence of glandular activity by the large numbers of dense-core vesicles produced by the Golgi apparatus. The axons contain synaptoidlike structures with surrounding clouds of vesicles; features analogous to known neurosecretory release sites.


The stichosome and its secretion granules in the mature muscle larva of Trichinella spiralis. The stichosome of the mature muscle larva of Trichinella spiralis consists of a single row of 45 to 55 stichocytes. Each stichocyte is about 25 mum in diameter and possesses a single nucleus. A duct leads from each stichocyte to the lumen of the esophagus. The stichocyte cytoplasm contains mitochondria, structures resembling Golgi-complexes, rough endoplasmic reticulum, and usually 1 of 2 types of secretory granules. The alpha-granule measures about 800 mn in diameter, contains a prominent inclusion, and has a granular matrix. The beta-granule is about 600 mn in diameter and is homogeneous in appearance. Both granule types are surrounded by a single membrane. Ten to thirteen stichocytes containing alpha-granules are confined to the posterior portion of the stichosome. After isopycnic centrifugation in sucrose gradient of large granule fractions obtained from cell-free homogenates, the alpha- and beta-granules show characteristic distribution patterns as revealed by the morphology of the fractions. The median equilibrium density of the alpha-granules is 1.245, while that of the beta-granules is 1.230. There is a correlation between the distribution of the granules and of antigens reacting with hyperimmune antitrichinella seruma. At least 4 unique antigens can be attributed to each of the granule types. Fractions enriched in mitochondria do not contain specific antigens. Antigens from both types of secretory granules cross react totally with those present in the excretion-secretion products of living muscle larvae. Cytoimmunochemical data show that antigens are distributed in a patchy fashion throughout the stichocyte cytoplasm. This finding is consistent with the distribution of the secretory granules in the intact stichocyte.


The Ornithodoros (Alectorobius) capensis group (Acarina: Ixodoidea: Argasidae) of the palearctic and oriental regions. O. (A.) maritimus: identity, marine bird hosts, virus infections, and distribution in western Europe and northwestern Africa. In 1967, Vermeil and Marguet described Ornithodoros coniceps maritimus from larvae reared from larvae taken from marine birds on Dumet Island (Atlantic Ocean), Basse Bretagne, France. We collected O. (A.) coniceps Canestrini, 1890, from the type locality (Venice, Italy) and determined that the taxons coniceps and maritimus each require full species status. We selected a lectotype and paralectotypes for the taxon maritimus from the original Dumet Island material. The larva of maritimus is redescribed and the nymph, male, and female are described for the first time. Collection data are recorded from Dumet and other islands off France, Aegimures Islands off Tunisia, Puffin Island off northern Wales, and Great Saltee Island off Ireland. This tick infests nesting colonies of the common tern, roseate tern, sandwich tern, herring gull (northern and Mediterranean races), common cormorant, shag, razorbill, common murre, black-legged kittiwake, and probably other marine birds nesting nearby. Adults and nymphs (tentatively identified as maritimus but lacking associated larvae for full confirmation) were taken near nests of the little egret in Lake Tunis, Tunisia. Soldado virus was isolated from Puffin Island tick samples and a Soldado-like virus from Great Saltee Island tick samples. An experimental study of West Nile virus in the Tunisian tick population is reviewed. The birds species associated with maritimus in each collecting locality, and their nesting and resting habits and migration patterns in relation to tick and arbovirus survival and distribution, will be reported in the following paper in this series.


Peripheral nervous system of the ticks, Amblyomma tuberculatum Marx and Argas radiatus Railliet (Acari: Ixodoidea). The peripheral nervous system of an ixodid and an argasid tick include the following components: (1) paired optic, cheliceral and pedipalpal nerves and unpaired stomodeal nerve arising from the pre-esophageal portion of the central nervous system (synganglion); (2) 4 pairs of pedal nerve trunks (each with appendicular and hemal branches) and 4 major pairs of opisthosomal nerves (including the paraspiracular, genital, postlateral-myosomal, and ano-myosomal nerves); and (3) the lateral "sympathetic" plexuses formed by contributions of hemal nerves arising from pedal ganglia and from the paraspiracular nerves. The salivary glands are multiply innervated by 4 pairs of nerves. The 1st pair arise from the pedipalpal nerves, the 2nd and 3rd from the lateral sympathetic plexuses, and the 4th from the paraspiracular nerves. Portions of the integument and the majority of non-appendicular muscles are innervated by various fine nerves arising from the lateral sympathetic plexuses and from the 4 pairs of opisthosomal nerves.


Study of neonatal gastric aspirate related to amniotic fluid and to the occurrence of the idiopathic respiratory distress syndrome. The lecithin/sphingomyelin ratio (L/S) has been shown to be of use in the prediction of the idiopathic respiratory distress syndrome (I.R.D.S) when performed on amniotic fluid. Gastric contents at birth consist mainly of amniotic fluid. Our study was designed to determine what the relationship was between the L/S ratios of amniotic fluid and gastric aspirate obtained at birth and to examine whether the L/S ratios of gastric aspirate was of any value in the prediction of I.R.D.S.


Theoretical isotropic dissolution of nonspherical particles. Equations are derived for the isotropic dissolution of single particles, considering simple forms of the six crystal systems. These can be summarized by three basic equations which are approximated well, and in some cases exactly, by the dissolution equation for a hypothetical spherical particle of specified diameter. Formulas are given to enable calculation of this diameter and to minimize the weighted errors in the approximations. Spherical approximations provide a simple basis for calculating the dissolution profile of real multiparticulate systems which are difficult to describe otherwise. Spherical approximations based on equal surface area or volume result in large errors.


Experimental evaluation of three single-particle dissolution models. The dissolution of the 60-85-mesh fraction os recording, flow-through dissolution apparatus equipped with a dissolution cell; it was particularly suitable for kinetic analysis of multiparticulate systems. By using a time-scaling approach, experimental data are compared with theoretical calculations to evaluate, quantitatively, which of three single-particle dissolution models best describes the data and how well the multiparticulate kinetics can be explained mathematically. The nonspherical tolbutamide particles are replaced in the calculations by a hypothetical system of spherical particles that appears to be log-normally distributed. This procedure permits the calculation of the intrinsic dissolution profile, considering both size distribution and particle shape effects.


Antioxidant efficiency of polyhydric phenols in photooxidation of benzaldehyde. An experimental system is described for the observation  of the kinetics of photochemically initiated oxidation reactions; this system is based on the measurement of oxygen consumption with a polarographic oxygen electrode. The photooxidation of benzaldehyde in dilute aqueous solution was examined and appears to conform to a free radical chain mechanism. The antioxidant efficiency of some polyhydric phenols was determined kinetically and found to be catechol greather than pyrogallol greater than hydroquinone greather than resorcinol greater than n-propyl gallate for the benzaldehyde photooxidation.


Photochromism of an anticonvulsant, 1-diphenylmethyl-4-(6-methyl-2-pyridylmethylene-amino) piperazine, in the solid state. The light-induced color change of 1-diphenylmethyl-4-(6-methyl-2-pyridylmethyleneamino) piperazine in the solid state was investigated. Light in the 420-700-nm visible region had no effect. Elevated temperature, dissolution, or prolonged storage in the dark at room temperatures restored the intrinsic color of the compound. IR, UV (solution), NMR, differential scanning calorimetry, and GC methods showed no detectable difference between the long wave-length UV light-exposed (yellow) and unexposed (colorless) samples of the pure compound. Long wavelength UV light exposure studies with several substituted piperazine analogs revealed a structure-activity requirement for the color conversion process. The data indicated that the transformation process from colorless (or faint yellow) to bright yellow is photochromism (phototropy) and is dependent on the intensity of the "action spectrum" in the 300-400-nm region. Studies in the solid state showed that heat-induced fading of the color followed apparent zero-order kinetics. The energy of activation, Eb, for the photochromic conversion process from the metastable (yellow) to the stable (colorless) state was estimated to be about 19 kcal/mole.


Interaction of sodium alkyl sulfates with everted rat small intestinal membrane. The effect of sodium alkyl sulfates (C6-C14) on the loss of protein from the everted rat small intestine was measured. At a surfactant concentration of 10 mM, a peak effect on protein release was noted with sodium decyl sulfate (C10). Measurement of proten release as a function of sidium lauryl sulfate (C12) concentration resulted in the observation that the effect appears to be due to the micellar phaseof the surfactant solution. At concentrations of C12 above the CMC, the loss of protein from the intestinal preparation increased as the concentration of surfactant was increased. There may be a maximum amount of protein that can be released from the everted rat small intestinal sacs by surface-active agents. At equivalent micellar concentrations of C8-C14 (12.5 times the CMC), there was no difference in the amount of protein released in the presence of the individual alkyl sulfate solutions. Other studies on salicylate transfer across the everted rat small intestine indicate that permeability changes occur with anionic and cationic surfactants but not with nonionics.


Automated fluorometric analysis of epinephrine in lidocaine hydrochloride injection. A rapid automated method for determining epinephrine in lidocaine hydrochloride injection is presented. The method is an adaptation of the official USP XIX fluorometric procedure and yields equivalent results. The linearity, accuracy, precision, excipient/background effect, and carryover characteristics of the automated system are described. A recovery study indicated that intact epinephrine is measured accurately in the presence of its degradation products. Analysis of several commercial preparations is reported.


Clofibrate microcapsules: preparation and release rat studies. Microencapsulation of clofibrate and dissolution characteristics of clofibrate microcapsules were investigated. Spherical droplets of clofibrate, prepared by a capillary jet method, were encapsulated in gelatin by simpel coacervation, using sodium sulfate as the coacervating agent. The microcapsules, which were hardened up to 8 hr with formaldehyde, were recovered as discrete, free-flowing particles. Dissolution of clofibrate from the microcapsules was not adequately described by either square root of time or Langenbucher kinetics but followed predominantly zero-order release patterns at all hardening times. A linear correlation was found between the hardening times and the t50% release time.


Synthesis of potential mescaline antagonists. 1-[2-(3,4,5-Trimethoxyphenyl)ethyl]-3-pyrroline, 2-(3,4,5-trimethoxybenzyl)-1,2,3,6-tetrahydropyridine, N-n-propylmescaline, N-cyclopropylmethylmescaline, and N-allylmescaline were synthesized as potential mescaline antagonists. The ability of these compounds to antagonize mescaline-induced disruption of swim behavior is also given.


Dissolution behavior and bioavailability of phenytoin from a ground mixture with microcrystalline cellulose. The ground mixture of phenytoin and microcrystalline cellulose was prepared by grinding in a vibrational ball mill. The X-ray diffraction patterns indicated the amorphous nature of the ground mixture. Comparative studies were made concerning the in vitro dissolution and in vivo absorption of fine phenytoin powder, phenytoin sodium powder, and the ground mixture. The ground mixture showed a greater dissolution rate than the fine powder and attained supersaturation in the pharmacopeial disintegration media at pH 1.2 and 7.4. In vivo absorption studies of each preparation were carried out in five subjects, using a crossover design, by measuring the urinary excretion rate of a main metabolite, 5-(p-hydroxyphenyl)-5-phenylhydantoin. The blood levels of phenytoin and the corresponding urinary excretion patterns of the metabolite were determined in two subjects. The ground mixtures significantly improved the bioavailability of phenytoin. The drug was completely and rapidly absorbed after oral administration of the ground mixture. The vibrational ball milling technique for a poorly water-soluble drug with microcrystalline cellulose provides a promising way of improving the in vivo drug absorption.


Solubility of nonelectrolytes in polar solvents IV: nonpolar drugs in mixed solvents. The molecular and group surface area approach to solubility is shown to be applicable to mixed aqueous solvent systems. An equation is derived which is consistent with the exponential increase in the aqueous solubility of nonpolar drugs that frequently accompanies the addition of a cosolvent. This equation predicts that: (a) the ability of a drug to be solubilized by a cosolvent is proportional to its hydrophobic surface area per molecule, and (b) the ability of a cosolvent to solubilize any drug is inversely proportional to its interfacial tension against a reference liquid hydrocarbon. These predictions are experimentally verified with solubility studies of several alkyl p-aminobenzoates in propylene glycol-water mixtures and of hexyl p-aminobenzoate in mixtures of water the ethanol, methanol, ethylene glycol, propylene glycol, glycerin, and formamide.


Bioavailability of 11 sulfisoxazole products in humans. Single lots of 11 commercially available 500-mg sulfisoxazole tablets were evaluated in vitro and in vivo. All products tested met USP XVIII specifications for weight variation and product assay. However, three products failed to meet the USP XVIII dissolution requirement. The only statistically significant difference observed between the 11 products was a lower peak plasma level exhibited by one product. No useful correlation was observed between the in vivo and in vitro studies for the dosage forms tested.


Effect of certain drugs in perfused human placenta XII: autacoid antagonism by phenothiazines. The effects of chlorpromazine, prochlorperazine, and trifluoperazine on the pressor actions of serotonin, angiotensin, and bradykinin in the perfused vessels of full-term human placentas were investigated. A significant inhibition of the effect of serotonin was observed with trifluoperazine and chlorpromazine but not with prochlorperazine. The inhibition is attributed to the ability of phenothiazines to cause adrenergic blockade. Because both bradykinin and angiotensin could not be consistently antagonized, it is concluded that they must act primarily via musculotropic mechanisms and only secondarily by stimulation of adrenergic receptors.


High-pressure liquid chromatographic analysis of tolbutamide in serum. A high-pressure liquid chromatographic (HPLC) analysis of tolbutamide in serum is described. The assay requires only 1 ml of serum and is capable of measuring as little as 2 mug of tolbutamide. The metabolites of tolbutamide do not interfere in the assay. Human serum samples, taken after a 1-g oral dose of tolbutamide, were analyzed by the HPLC and an existing GLC procedure, and the results are compared.


Prodrug approaches to enhancement of physicochemical properties of drugs IV: novel epinephrine prodrug. The synthesis and characterization of a prodrug that appears to overcome the problem of inefficient absorption of epinephrine through the lipoidal membranes of the eye are described. The enzymatic rate of regeneration of epinephrine from the prodrug was determined using a rabbit eye homogenate, rabbit plasma, and human plasma. The prodrug had no activity of its own when tested against a guinea pig smooth muscle preparation. Upon enzymatic regeneration of epinephrine from the prodrug, however, the reaction mixture exhibited alpha-adrenergic activity equivalent to that of epinephrine when tested in the same preparation.


Mass spectral analysis of glucuronides from sympathomimetic hydroxyphenylalkylaminoethanols. A mass spectral method is described for the structure determination of glucuronic acid conjugates of hydroxyphenylalkylaminoethanol-type drugs. Trimethylsilylation and application of the GLC-mass spectral technique yield mass spectra with sufficient information for the identification of all structural subunits.


In vitro release of therapeutically active ingredients from polymer matrixes. Several therapeutically active ingredients including benzocaine, cyclomethycaine, and methapyrilene hydrochloride were incorporated into ethylcellulose and polyamide films. The effect of cetyl alcohol and tributyl citrate upon the release of these ingredients was studied. The films containing the active ingredient and plasticizer were cast upon a mercury substrate, and the in vitro release of these drugs from each film into a desorbing medium of distilled water was measured. The results indicated that the film-forming agent and plasticizer affected the drug release rate and that the release followed first-order kinetics. Benzocaine was slowly released from polyamide-cetyl alcohol films and polyamide-cetyl alcohol-tributyl citrate films. Polyamide-tributyl citrate films showed enhanced release of benzoacaine and cyclomethycaine. Ethylcellulose films plasticized with tributyl citrate produced a fast drug release. Based upon these results, a water-soluble, highly polar, noncomplexing additive would tend to increase the drug release from the film. When the amount of benzocaine released from ethylcellulose was plotted as a function of the square root of time, a linear plot was obtained. Since this linear plot passed through the origin, ethylcellulose should be an ideal matrix for benzocaine according to the Higuchi diffusion-controlled model. These studies demonstrated the in vitro release of thf the solubility of the active agent in both the polymer film as a function of the solubility of the active agent in both the polymer matrix and the desorbing medium.


Determination of salicylates by GLC.

Determination of salicylates by GLC. Silylation of salicylic acid by hexamethyldisilazane, N,O-bis(trimethylsilyl)acetamide, and N,N-bis(trimethylsilyl)trifluoroacetamide was compared using GLC. The completeness of the reaction, the stability of products, and the reproducibility of results with time were investigated. Different reaction vessels were examined for their reliability and application for a routine assay procedure.


High-performance liquid chromatographic separation of C-15-epimers of 15-methylprostaglandin E2 methyl ester and 15-methylprostaglandin E2. A high-performance liquid chromatographic system that permits quantitation of 15-methylprostaglandin E2 and its methyl ester is described. Separation from the corresponding C-15 epimers is effected by adsorption chromatography on microparticulate silica with refractive index detection.


Comparison of observed and predicted first-pass metabolism of nortriptyline in humans. The extent of first-pass metabolism of nortriptyline, calculated by comparing the areas under the plasma concentration-time curves following intravenous and oral dosing in six individuals, varied from 41 to 54%. Theoretically predicted values ranged from 41 to 61% based on a plasma flow model, indicating that the clearance takes place mainly from the plasma, which does not represent the whole blood concentration.


Selectivity of 4-methoxyphenethylamine derivatives as inhibitors of monoamine oxidase. It has been established that the oxidative deamination of tyramine by monoamine xodase is inhibited by (+/-)-4-methoxy-beta-hydroxyphenethylamine and its N-methylated derivatives. This particular series of compounds does not inhibit the action of monoamine oxidase when tryptamine is used as the substrate. In contrast, 4-methoxyphenethylamine and its N-methylated homologs inhibit the monoamine oxidase-catalyzed deamination of both tyramine and tryptamine.


Volume of distribution and tissue level errors in instantaneous intravenous input assumptions. A comparison was made between instantaneous input assumption and short-term zero-order infusion for 1 and 2 min for several drugs showing fast distribution to the tissue compartments. The errors ranged from 9 to 40% for the volume of the central compartment, from 0.7 to 11% for the volume of distribution following pseudo-distribution equilibrium, and from 11 to 34% for the volume of distribution change at the end of the 2-min infusion period. Significant errors in the tissue levels also were observed. It was suggested that all intravenous administrations be considered as short-term zero-order inputs.


Stereochemistries of geometric isomers of 4-(2-bromo-1,2-diphenylvinyl)phenol, 4-(2-bromo-1,2-diphenyylamine: corrections of the literature. The stereochemistries of geometric isomers of 4-(2-bromo-1,2-diphenylvinyl)phenol, 4-(2-bromo-1,2-diphenylvinyl)anisole, and 2-[p-(2-bromo-1,2-diphenylvinyl)phenoxy]triethylamine were determined by conversion of the phenolic analog to the ethers and subsequent comparison of physical properties with those of 2-[p-(2-chloro-1,2-diphenylvinyl)phenoxy]triethylamine of known stereochemistry.


Antimicrobial activity of newly synthesized isothiocyanate derivatives against pathogenic plant microorganisms. Fifteen reaction products of isothiocyanates with cysteine, seven reaction products of isothiocyanates with 2,3-dimercapto-1-propanol, and four reaction products of isothiocyanates with sulfanilamide were synthesized. Their antimicrobial activity against pathogenic plant microorganisms was investigated.


Automated analysis of warfarin sodium tablets. An automated procedure was developed for the determination of warfarin sodium by following the steps of the manual USP procedure. The automated procedure is applicable to single tablets and composites of 20 tablets at different tablet concentrations. Sensitivity, precision, accuracy, and reproducibility are equivalent to the manual USP procedure. Sensitivity was approximately 15 mug/ml, with a coefficient of variation of 0.711%.


Sulfur analogs of psychotomimetic amines. The syntheses and physical properties are described for 2,5-dimethoxy-4-methylthiophenylethylamine and 2,5-dimethoxy-4-methylthiophenylisopropylamine. The latter compound is the sulfur analog of the psychotomimetic phenylisopropylamines 2,4,5-trimethoxyphenylisopropylamine and 2,5-dimethoxy-4-methylphenylisopropylamine wherein the methylthio group replaces a methoxy group or a methyl group, respectively. This compound is predicted to be about 30 times as active as mescaline.


Rapid procedure for assessment of compounds that modify uptake and release of tritiated norepinephrine. A rapid procedure to estimate tritiated norepinephrine (levarterenol) in a single mouse heart is described. The method is based upon oxidation of the tritium in the tissue to tritiated water, which is then determined by liquid scintillation spectroscopy. Large numbers of samples can be assayed with great facility. The effects of standard compounds that modify the uptake and release of 3H-norepinephrine in heart tissue were determined with this system, and a procedure for studying their interactions is described.


Critical analysis of "flip-flop" phenomenon in two-compartment pharmacokinetic model. Computer simulations were used to examine the effect of first-order absorption on the disposition of one- and two-compartment model drugs. Two-compartment systems that attain a clinically acceptable beta-phase after rapid intravenous injection were perturbed by introduction of drug via first-order absorption. The validity of perceiving such a system as a potential "flip-flop" model was tested by comparing the negative slopes of log-linear plasma-time profiles to known values for ka and beta for various values of ka, k12, k21, and k10. Although most log-linear plots showed excellent correlation coefficients (r2 greater than 0.996), their negative slopes (S) did not represent either ka or beta under various combinations. A similar consideration of the one-compartment model enabled a comparison to be made between the two systems. Maximum negative errors were observed for both one- and two-compartment drugs as ka leads to k2 or beta, respectively. The value for S provided a good estimate of the absorption rate constant, ka, when k2 greater than or equal 2ka (one compartment) or beta greater than or equal 2ka. The elimination rate constant (k2 or beta) could be obtained from S for all one-compartment and some two-compartment drugs when the value of ka was approximately twice that of k2 or beta. Large positive errors also were observed with certain two-compartment drugs where the ratio of the four rate constants apparently linearized a nonlinear plasma profile. Conditions wherein S may be expected to approach beta wherein S approaches ka are clearly defined.


Wettability of pharmaceutical solids: estimates of solid surface polarity. Contact angle measurements of water and methylene iodide with various organic solids were used to estimate the surface free energy per square centimeter, gammaS, and the contributions of nonpolar and polar forces, gammaSd and gammaSp, respectively. The ratio of gammaSp to gammaS was used as an estimate of solid surface polarity, and values ranging from 0 to 42% polarity were calculated for materials of pharmaceutical interest. Surface free energies per mole were calculated to compare the influence of different substituent groups on wettability. This approach offers a convenient means to quantitate the polarity of organic pharmaceutical solid surfaces.


Comparative evaluation of tablet lubricants: effect of application method on tablet hardness and ejectability after compression. The effect of four lubricants (stearic acid, magnesium stearate, calcium stearate, and talc) on the ejectability and hardness of statically compressed tablets of a lactose granulation was examined. Two methods of application of these lubricants, incorporation into the granulation and mixing with the granulation, were compared. In both methods, the energy consumption curves during ejection and the hardness curves with lubricant concentration were similar and showed complicated behavior at a lower concentration. The mixing method gave better results for ejectability and hardness than the incorporation method.


Kinetic analysis of penicillin degradation in acidic media. Degradation of penicillin in acidic media (pH 2.7) was monitored by high-pressure liquid chromatography and UV spectroscopy. The effects of temperature, buffer concentration, and ionic strength were examined. A degradation pathway is proposed, and the apparent first-order rate constant and energy of activation were calculated for each reaction. One or more degradation products containing a sulfhydryl group, a functional group often suggested as having a major role in eliciting allergic responses to penicillin therapy, were present throughout the degradation scheme.


Effect of intragranular and extragranular disintegrating agents on particle size of disintegrated tablets. Five materials were compared for their effectiveness as disintegrating agents: maize starch, sodium calcium alginate, alginic acid, microcrystalline cellulose, and a colloidal aluminum silicate. The effect of the proportion of the agent present and the position with respect to the granule, intra- and extragranular, was examined. The extragranular formulations disintegrated much more rapidly than the intragranular ones, but the latter gave a much finer dispersion of particles. A combination of intra- and extragranular disintegrating agents gave the best compromise; of those tested, the alginates appeared to effect the breakdown to the smallest particles when placed intragranularly. A method of assessing the effectiveness of disintegrating agents for uncoated tablets is suggested, but the resulting weight mean particle size is the more important criterion for tablets complying with a pharmacopoeial disintegration test. The porosity and crushing strength of tablets are useful as guides to disintegration only when a given formulation is used.


Quantitative determination of theophylline in pharmaceutical dosage forms by differential spectrophotometry. Theophylline was determined with good precision in tablets and capsules by differential spectrophotometry. Xanthines such as caffeine and theobromine did not interfere providing the total xanthine concentration was kept below 100 mug/ml. At a higher total xanthine concentration, nonlinearity occurred, presumably due to complex formation. This interference could be minimized by proper selection of the analytical wavelength.


Physical aspects of wet granulations II: factors involved in prolonged and excessive mixing. Evidence is presented that excessive blending in a wet granulation process shifts the packing arrangement of the wet granule, causing it to become dense and nonporous. With prolonged kneading, a large amount of the water-soluble excipients dissolves in the granulating fluid, and these two factors make the drying slower. This result, coupled with the previous finding that a certain time is required to attain an equilibrium size granule, explains why there exists an optimum kneading time for a wet granulation from a mechanical performance point of view.


Pharmaceutical applications of solid dispersion systems: dissolution of griseofulvin-succinic acid eutectic mixture. The dissolution profile of the griseofulvin-succinic acid eutectic mixture system was evaluated using the powder and constant-surface are tablet methods. Factors contributing to the enhancement of griseofulvin dissolution from the dispersion in succinic acid are discussed. Contrary to the original proposal of Sekiguchi and coworkers, dissolution rates of driseofulvin from solid dispersions were found to be markedly affected by the particle size of solid dispersions.


Application of trichloroacetyl isocyanate to NMR analysis of steroids of pharmaceutical interest I: corticosteroids and chemically related compounds. The trichloroacetyl carbamates of 38 corticosteroids and chemically related compounds were prepared, and their NMR spectra in deuterochloroform were obtained. The effects of the introduction of a number of functional groups on the chemical shift of the carbamate proton signals were determined.


Drug biotransformation interactions in man VI: acetaminophen and ascorbic acid. Oral administration of 3 g of ascorbic acid 1.5 hr after an oral dose of 1 g of acetaminophen caused a rapid and pronounced decrease in the excretion rate of acetaminophen sulfate in five healthy adult volunteers. There was a statistically significant increase in the fractions of the dose of acetaminophen excreted as such as as acetaminophen glucuronide but a decrease in the fraction excreted as acetaminophen sulfate. The apparent biological half-life of acetaminophen increased from 2.3 +/- 0.2 (mean +/- SD) to 3.1 +/- 0.5 hr. Concomitant administration of sodium sulfate prevented these effects. Ascorbic acid, which itself is metabolized in part to the sulfate, inhibits the conjugation of acetaminophen with sulfate by competing for available sulfate in the body.


Structural functions of taste in the sugar series VII: taste properties of ketoses. The preferable structural feature for sweetness is a lipophilic moiety, e.g., a five- or six-membered ring with a polar substituent containing an A-H/B system outside the ring. In ketoses, this unit is probably the 1,2-glycol. If a third feature (the lipophilic, gamma, site) is required for the attainment of optimum sweetness and if it is C-6 in ketoses, then this site can accommodate quite a large constituent, both above and below the plane of the ring. The removal of the hydroxyl group from the C-6 hydroxymethyl substituent to yield the 7-deoxy derivatives causes bitterness, thus implicating the primary hydroxymethyl group with bitterness.Therefore, the creation of lipophilic site(s) in the sugar ring causes the realignment of the sugar molecule on the taste receptor surface. The distrubance of the proposed A-H/B system, e.g., the removal of the C-2 hydroxyl group, causes the ring alpha-glycol unit (most likely the ring C-3 and C-4 hydroxyl groups) to function as the A-H/B system.


Molecular connectivity V: connectivity series concept applied to density. The concept of the expanded series of the connectivity index, chi, is introduced and applied to a consideration of the density of three classes of molecules. Correlations are found using two terms in the expanded series. A preliminary reflection on the extended series terms is made. It is noted that the regression equation constant in the three studies is close to the phase volume, 0.7402, and the possible significance of this fact is discussed.


Computerized automated system for determining dissolution rate profiles for solid dosage forms. A unique automated system was developed for the measurement of dissolution rates of tablets and capsules. This system, which adheres to principles set forth in the compendia, can test six dosage forms simultaneously. It is modular in form and capable of maintaining sink conditions, and it can handle any type of chemistry amenable to an automatic analyzer. In addition to the usual dissolution apparatus, the system includes a 12-channel combination sampling and solvent addition pump, a sequence control module, pertinent automated analyzer components, a spectrophotometer or fluorometer, an optional recorder, a specially designed digitizing system, and a teletype equipped with a paper tape punch reader and acoustic coupler. Each dissolution flask is automatically sampled every 6 min. Standards may be run either before or after the samples. Since dissolution, sampling, chemistry, and readout are all accomplished simultaneously, the complete test time is essentially reduced to the dissolution time itself. At the completion of sample dissolution, raw dissolution profile data are on the punched paper tape ready for computer processing via a time-sharing system. Developed software provides for the printout of a complete test report in less than 15 min.


Sensitive GLC procedure simultaneous determination of phenytoin and its major metabolite from plasma following single doses of phenytoin. An improved GLC procedure was developed for the simultaneous determination of phenytoin and its metabolite, 5-(p-hydroxyphenyl)-5-phenylhydantoin, in plasma and urine following enzyme hydrolysis. After extraction, the drug, the metabolite, and the internal standard, 5-(p-methylphenyl)-5-phenylhydantoin, are measured by GLC with flame-ionization detection as their respective methyl derivatives following flash-heater methylation with trimethylanilinium hydroxide. The drug and metabolite give well-resolved symmetrical peaks on a phenyl methyl silicone column, and the method has a sensitivity of 150 ng/ml of phenytoin and 125 ng/ml of the metabolite. GLC-mass spectral evidence is presented for the formation and intact determination of methyl derivatives of the drug, its metabolite, and the internal standard.


Synthesis of 1,2-dioleoyl-3-(alpha-14C-1-adamantoyl)-sn-glycerol and 1-14C-adamantanecarboxylic acid. The pancreatic lipase inhibitor 1,2-dioleoyl-3-(alpha-14C-1-adamantoyl)-sn-glycerol, with a specific activity of 8 mCi/mmole, was prepared by consecutive acylation of 1,2-isopropylidene-sn-glycerol with 1-14C-adamantanecarboxylic acid chloride and oleoyl chloride. The 14C-labeled acid was conveniently prepared by carboxylation of 1-adamantanol using 14C-sodium formate in concentrated sulfuric acid.


Anticonvulsant activity of enzyme inhibitors in rats. Three liver microsomal enzyme inhibitors, proadifen, 2,4-dichloro-6-phenylphenoxyethyldiethylamine, and 2,4-dichloro-6-phenylphenoxyethylamine, and a hepatotoxic agent, carbon tetrachloride, were tested for anticonvulsant activity in adult male albino rats using the maximal electroshock seizure technique. All four substances exhibited significant anticonvulsant activity 1 hr after intraperitoneal administration. This protection was absent when tested 24 hr later.


Antiradiation compounds XVI: N-heterocyclic aminoethyl disulfides and aminoethanethiosulfuric acids. A series of N-heterocyclic and N-heterocyclic alkyl derivatives of bis(2-aminoethyl) disulfide and aminoethanethiosulfuric acid was synthesized as potential antiradiation and anticancer agents. The compounds were prepared by the reactions of the heterocyclic halides with bis(2-aminoethyl) disulfide and aminoethanethiosulfuric acid. A dithio acid derivative, 3,3-dimercapto-2-cyanoacryloylpyrrolidide, was also prepared. Several compounds, including the dithio acid derivative, provided good radiation protection to mice. None of the compounds screened showed appreciable anticancer activities in two leukemia systems.


Gravimetric determination of chlorhexidine using tetraphenylborate ion. A precise and accurate gravimetric procedure was developed for the determination of chlorhexidine diacetate, digluconate, or dihydrochloride. Sodium tetraphenylborate solution was the precipitant in an acidic medium (pH 1). Tablets containing both chlorhexidine diacetate and benzocaine also were assayed.


GLC determination of cyclobenzaprine in plasma and urine. A GLC determination of cyclobenzaprine in human plasma and urine is described. After extraction from alkalinized samples with heptane-isopentyl alcohol (97:3), the drug and internal standard were back-extracted into 0.1 N HCl and then reextracted into ether. Use of a lower homolog of the drug as an internal standard was effective in reducing variability. Drug concentrations as low as 25 ng/ml could be assayed with high precision. Plasma levels in humans given 40 mg po or iv ranged from 5 to 51 ng/ml; little unchanged cyclobenzaprine was present in the urine. The N-desmethyl analog of the drug was detected as a metabolite in urine.


IR spectroscopic characterization of 2-thiohydantoins and 2-thiobarbiturates. A characterization of 2-thiohydantoins and 2-thiobarbiturates by IR spectra is proposed, using three characteristic group frequencies: the "thioureide band" around 1500 cm-1 and the antisymmetric-symmetric stretching modes of NCS bonds around 1400 and 1200 cm-1. The general characteristic absorption areas are found by comparison with N-phenylthioureas and thioanilides.


On the statistics of drug-receptor constants for partial agonists. A linear relationship between equieffective concentrations of agonist in the presence and absence of partial agonist was examined statistically. These experimental concentrations permit the estimation of the apparent dissociation constant Kp with a weighted fit. The form of the weights was proposed theoretically and substantiated by simulated experiments. Constants Kp for (+/-)-p-chloroisoproterenol were estimated from the antagonism by three concentrations of (+/-)-p-chloroisoproterenol of the positive chronotropic effects of (-)-isoproterenol on kitten (Kp = 1.75 X 10(-7) M) and guinea-pig (Kp = 1.84 X 10(-7) M) right atria. The Kp values were similar regardless of the concentrations of (+/-)-p-chloroisoproterenol used; they were also similar to a Kp of 1.95 X 10(-7) M) estimated BY Kaumann and Birnbaumer (J. Biol. Chem. 249: 7874-7885, 1974) for the (+/-)-p-chloroisoproterenol-receptor complex coupled to the adenylyl cyclase in cell-free membrane particles of kitten heart. The proposed statistical procedure appears to be useful for systems with sigmoid log concentration-effect curves in which concentrations of the dependent variable are obtained from interpolation.


The role of acetylcholine receptors and acetylcholinesterase activity in the development of denervation supersensitivity. Strips of muscle from innervated and denervated rat hemidiaphragm were tested for sensitivity to acetylcholine and to carbachol. For both agonists, denervation (6-8 days) produced notable supersensitivity. However, the increase in sensitivity to acetylcholine (ca. 600-fold) was much greater than that to carbachol (ca. 51-fold). Denervation also produced an increase in [3H]alpha-bungarotoxin binding (ca. 20-fold), presumably indicative of an increase in the number of acetylcholine receptors. In addition to causing increases in tissue sensitivity and receptor number, denervation caused a marked loss of acetylcholinesterase activity (ca. 70%) and a modest loss of butyrylcholinesterase activity (ca. 20%). When innervated muscle was pretreated with eserine (5 X 10(-5) M), there was a loss of acetylcholinesterase activity (ca. 86%) and butyrylcholinesterase activity (ca. 36%). Simultaneously, there was an increase in tissue sensitivity to acetylcholine (ca. 26-fold). When denervated muscle was pretreated with eserine, there was no loss of enzyme activity beyond that caused by denervation. Furthermore, eserine pretreatment did not increase denervated muscle sensitivity to acetylcholine. The data suggest that both an increase in acetylcholine receptors and a decrease in acetylcholinesterase activity contribute to the phenomenon of denervation supersensitivity.


Stimulation of glycogenolysis by beta adrenergic agonists in skeletal muscle of mice with the phosphorylase kinase deficiency mutation (I strain). The mechanism by which beta adrenergic agonist stimulate glycogenolysis in intact skeletal muscle was investigated in mice with the phosphorylase kinase deficiency mutation (I strain). Although extracts of I strain diaphragm muscle had only 3.7% of the phosphorylase kinase activity found in extracts of the control strain (C57BL), incubation of I strain hemidiaphragms in Krebs-Ringer bicarbonate buffer with either isoproterenol or epinephrine resulted in a stimulation of the rate of glycogenolysis. In C57BL diaphragms, the EC50 values for isoproterenol and epinephrine were 2 and 14 nM, respectively. With I strain diaphragms, dl-isoproterenol or l-epinephrine stimulated glycogenolysis as a linear function of the log of the drug concentration with no apparent plateau of response up to concentrations of 30 to 40 mugM. For each 10-fold increase in drug concentration, isoproterenol and epinephrine stimulated glycogenolysis in I strain muscles an additional 0.37 to 0.42 mg/g/hr, a slope in the concentration-response relationship of 0.17 and 0.37, respectively, of that measured in C57BL diaphragms at concentrations around the EC50. The highest glycogenolytic response measured in I strain hemidiaphragms (at 40 mugM isoproterenol) was 80% of the maximal catecholamine-stimulated glycogenolysis in C57BL diaphragms. Both 4 nM and 4 mugM isoproterenol, in a concentration-dependent manner, stimulated phosphorylase b to a conversion in I and C57BL diaphragms and increased cyclic adenosine 3':5'-monophosphate (cyclic AMP) concentrations. The glycogenolytic response to 10.1 nM dl-isoproterenol in both I and C57BL diaphragms was blocked by 34 nM l-propranolol but not by 34 nM d-propranolol. The response to 4 mugM isoproterenol was enhanced by the cyclic nucleotide phosphodiesterase inhibitors papaverine (27 mugM) or dl-4-(3-butoxy-4-methoxybenzyl)-2-imidazolidinone (Ro 20-1724, 3 mugM). From the results of these studies, we conclude: 1) Catecholamines stimulate glycogenolysis in skeletal muscle of I mice, as in C57BL mice, by interacting with the beta adrenergic receptor, thereby increasing tissue cyclic AMP concentrations and stimulating phosphorylase b to a conversion. 2) alternative hypotheses for the mechanism of the catecholamine-stimulated decrease in glycogen concentration in I skeletal muscle-inhibition of glycogen synthesis, hyposia and 5'-AMP stimulation of phosphorylase b activity-have been ruled out. 3) the activity of the mutant phosphorylase kinase, although it is only 3.7% of that in extracts of C57BL muscle, is sufficient to produce phosphorylase b to a conversion and thereby account for the glycogenolytic response of I strain muscle to catecholamines.


Serotonin accumulation in the guinea-pig myenteric plexus: ion dependence, structure-activity relationship and the effect of drugs. The specific accumulation of serotonin in neurons of the guinea-pig myenteric plexus was examined. Nonadrenergic neurons have been shown to be responsible for this accumulation. Serotonin accumulation, known to be sodium-dependent, was found to be inhibited by elevating the external potassium concentration. Accumulation was inversely related to the concentration of potassium and was also decreased in the presence of 0 mM Ca++ or 12 mM Ca++. The affinity of analogous molecules for the myenteric plexus was greatly reduced in compounds which had no alkyl amino side chain, in which the amino group was methylated or which had no 5-hydroxyl group. Most analogs competitively inhibited serotonin accumulation and 6-hydroxytryptamine was demonstrated by histofluorescence to be taken up into the myenteric plexus after chemical sympathectomy with 6-hydroxydopamine. Serotonin accumulation was also inhibited by tricyclic antidepressants and amphetamines. The inhibition of serotonin accumulation by these compounds differed from their inhibition of  accumulation of norepinephrine. As in the central nervous system, chlorimipramine was the most potent tricyclic antidepressant against accumulation of serotonin while desmethylimipramine was the most potent inhibitor of the accumulation of norepinephrine. Amphetamines were more effective inhibitors of serotonin accumulation than were tricyclic antidepressants, but all of these drugs were more effective against the accumulation of norepinephrine than serotonin. This study confirms the existence of a unique population of axons int he mammalian myenteric plexus which are distinguishable by their characteristic accumulation of serotonin and have not been found elsewhere in the peripheral nervous system.


Functional evaluation of 6-hydroxydopamine-induced sympathectomy in the liver of the cat. Intraportal injection of 6-hydroxydopamine (25 mg/kg) results in nearly complete functional sympathectomy in the cat liver 1 week after the injection. Functional sympathectomy was verified by comparing the changes in liver blood volume (measured in vivo in a plethysmograph) resulting from direct stimulation of the hepatic nerves in control and pretreated animals. Pretreatment prevented the large reductions in hepatic blood volume normally seen with nerve stimulation while the response to infused noradrenaline was not reduced. Lack of morphological changes in right atrial nerve endings and an unaltered pressor response to bilateral carotid arterial occlusion indicate that sympathectomy at sites other than the liver did not occur.


In vitro denervation of the portal vein and caudal artery of the rat. The effects of 6-hydroxydopamine (6-OHDA) on the isolated portal vein and caudal artery of the rat were studied to investigate the possibility of producing in vitro adrenergic denervation of these blood vessels. Loss of nerve function was determined by field stimulation of the nerves, using short pulses, and by 3H-norepinephrine (NE) uptake. Addition of 6-OHDA produced contractions of both veins and arteries. Two hours after treatment with 6-OHDA, the contractile responses of the caudal arteries and portal veins to field stimulation were reduced to undetectable levels. At this point, the vessels were unable to take up 3H-NE and incubation of the preparations with l-NE failed to restore the contractile responses to nerve stimulation. Prejunctional supersensitivity to l-NE was observed in the portal vein after 6-OHDA but hot in helically cut strips of caudal artery. Prejunctional supersensitivity of the caudal artery to NE was seen, however, if the vessel geometry was kept intact, suggesting that the uptake mechanism for catecholamines only plays a major role in the termination of action of exgenous NE when norepinephrine is applied through the nerve plexus. We conclude that in vitro treatment with 6-OHDA rapidly produces functional adrenergic denervation of both portal vein and caudal artery of the rat and provides an accurate assessment of the importance of the neuronal uptake mechanism to NE sensitivity.


Adrenergic neuronal degeneration induced in portal vein and caudal artery by 6-hydroxydopamine in vitro. Fluorescence histochemistry and electron microscopy were used to study the structural consequences of in vitro exposure to the sympatholytic agent 6-hydroxydopamine on two blood vessels, the portal mesenteric vein and caudal artery of the rat. The results showed depletion of catecholamines to indetectable levels associated with clear signs of adrenergic nerve degeneration, such as cytoplasmic shrinking, virtual absence of dense core vesicles and swelling of mitochondria. All of the changes observed occurred within 2 hours in the caudal arteries and 3.5 hours in the portal veins. Comparison of electron and fluorescence micrographs of incubated control specimens with those of unincubated, fresh specimens showed that the nerve endings of the incubated controls were well preserved for at least 3.5 hours. With destruction of nerve endings in such a short period of time, the processes of specific neuronal degeneration could be clearly demonstrated in isolated blood vessels.


Influence of neonatal and adult hyperthyroidism on behavior and biosynthetic capacity for norepinephrine, dopamine and 5-hydroxytryptamine in rat brain. In neonatal rats, administration of l-triiodothyronine (10 mug/100 g/day) for 30 days presented signs of hyperthyroidism which included accelerated development of a variety of physical and behavioral characteristics accompanying maturation. The spontaneous motor activity was increased by 69%. Exposure of developing rats to thyroid hormone significantly increased the endogenous concentration of striatal tyrosine and the activity of tyrosine hydroxylase as well as the levels of dopamine in several brain regions. The concentration of striatal homovanillic acid and 3,4-dihydroxyphenylacetic acid, the chief metabolites of dopamine, was also increased and the magnitude of change was greater than the rise in dopamine. Despite increases in the activity of tyrosine hydroxylase and the availability of the substrate tyrosine, the steady-state levels of norepinephrine remained unaltered in various regions of brain except in cerebellum. Futhermore, neonatal hyperthyroidism significantly increased the levels of midbrain tryptophan and tryptophan hydroxylase activity but produced no change in 5-hydroxytryptamine levels of several discrete brain regions, except hypothalamus and cerebellum where its concentration was slightly decreased. However, the 5-hydroxyindoleacetic acid levels were enhanced in hypothalamus, ponsmedulla, midbrain, striatum and hippocampus. The elevated levels of 5-hydroxyindoleacetic acid did not seem to be due to increased intraneuronal deamination of 5-hydroxytryptamine since monoamine oxidase activity was not affected in cerebral cortex and midbrain of hyperthyroid rats. The data demonstrate that hyperthyroidism significantly increased the synthesis as well as the utilization of catecholamines and 5-hydroxytryptamine in maturing brain. Since the mature brain is known to respond differently to thyroid hormone action than does the developing brain, the effect of L-triiodothyronine treatment on various putative neurohumors also was examined in adult rats. Whereas administration of l-triiodothyronine (10 mug/100 g/day) for 30 days to 120-day-old rats increased the levels of tyrosine by 23% and of tryptophan by 43%, no appreciable change was noted in tryptophan hydroxylase activity. In contrast to neonatal hyperthyroidism, excess of thyroid hormone in adult rats failed to produce any change in motor activity and tended to decrease striatal tyrosine hydroxylase activity only slightly. The concentration of dopamine remained unchanged in all regions of the brain except in midbrain where it rose by 19%. Whereas norepinephrine concentration was altered in hypothalamus, pons-medulla and midbrain, the levels of 5-hydroxytryptamine and its metabolite, 5-hydroxyindoleacetic acid, were significantly decreased in striatum and cerebellum. Since dopaminergic and noradrenergic neurons are the critical components of the motor system, the possibility exists that elevated behavioral activity in young L-triiodothyronine-treated animals might be associated with increased turnover of catecholamines in neuronal tissue.


Tryptoline inhibition of serotonin uptake in rat forebrain homogenates. We have examined the effects of six tryptolines (tetrahydro-beta-carbolines) upon 5-hydroxytryptamine (5-HT) uptake into rat forebrain homogenates. All six were found to be competitive inhibitors of 5-HT uptake. 5-Hydroxytryptoline, the most potent inhibitor, had an inhibitor constant (Ki) of 0.3 mugM. Both 5-hydroxytryptoline and 5-hydroxymethtryptoline were also shown to be relatively selective against 5-HT uptake, being 20 times less potent against norepinephrine uptake and 40 times less potent against dopamine. Since it is possible that tryptolines might be formed as a result of alcohol consumption, these results suggest that it is important to examine the possibilities that such compounds mediate some of the effects of alcohol upon serotonergic pathways.


The existence of tolerance to and cross-tolerance between d-amphetamine and methylphenidate for their effects on milk consumption and on differential-reinforcement-of-low-rate performance in the rat. Administration of d-amphetamine (2.5 mg/kg) or methylphenidate (20 mg/kg) decreased milk consumption in rats. When these drugs were administered daily, tolerance developed to this effect over the course of 20 days. Cross-tolerance to the effects on milk consumption occurred between d-amphetamine and methylphenidate over a 4-fold range of dose of both drugs. Administration of d-amphetamine (1.5 mg/kg) or methylphenidate (10 mg/kg) disrupted responding under differential-reinforcement-or-low-rate (DRL) contingencies. Both drugs increased response rate, decreased frequency of reinforcement and shifted the mode of the inter-response time distribution to the left. When the drugs were administered daily, tolerance developed to all these effects over the course of 20 days. Cross-tolerance to the effects on DRL behavior occurred between d-amphetamine and methylphenidate over a 4-fold range of dose of both drugs. Daily administration of d-amphetamine (2.5 mg/kg) but not of methylphenidate (20 mg/kg) resulted in decreased norepinephrine (NE) levels in brain; the decreased norepinephrine levels, which occur with repeated d-amphetamine administration, are believed to result from the storage in noradrenergic neurons of p-hydroxynorephedrine, a metabolite of d-amphetamine. Radioactivity was not detectable in brain 24 hours after the last of 15 daily doses of radiolabeled methylphenidate. These results suggest that d-amphetamine, but not methylphenidate, is metabolized to a compound which is stored in noradrenergic neurons. The existence of behavioral cross-tolerance between d-amphetamine and methylphenidate is therefore inconsistent with the hypothesis that tolerance to the behavioral effects of d-amphetamine is due to the metabolism of d-amphetamine to p-hydroxynorephedrine, a false transmitter in noradrenergic neurons.


Studies on the effect of 5,5'-diphenylhydantoin on in vitro protein synthesis in rat brain. Previous investigators have reported binding of the drug 5,5'-diphenylhydantoin (DPH) to RNA and DNA and an effect of this compound on protein synthesis. We have studied the effect of DPH on in vitro protein synthesis by investigating the possible role of this drug on poly-Uracil-directed polyphenylalanine synthesis and natural mRNA-directed amino acid incorporation into polypeptides. There was no demonstrable effect of DPH on either of these reactions. It was also found the DPH did not alter the rate of aminoacylation of purified rat liver tRNAs. The in vivo daily administration of DPH to animals for a period of 2 weeks did not appear to affect the in vitro poly-Uracil-directed polyphenylalanine synthesis (chain elongation aspects of protein synthesis) in adult rat brain. It was also found that DPH did not inhibit DNA-dependent RNA synthesis as catalyzed by RNA polymerase. These studies do not support the hypothesis that DPH plays a role in protein synthesis in adult brain cells.


Anticonvulsant action of acute morphine administration in rats. The effect of acute administration of morphine on cerebral excitability was investigated in rats with two convulsant drugs: flurothyl (hexafluorodiethyl ether) and pentylenetetrazol (PTZ). In the flurothyl study, adult male Sprague-Dawley (S-D) rats were injected subcutaneously with morphine sulfate in doses ranging from 0.5 to 256 mg/kg. At 15, 30, 60 and 120 minutes after morphine injection, flurothyl was administered by inhalation and the seizure thresholds were determined. In the PTZ study, 64 mg/kg of morphine sulfate were injected subcutaneously into both S-D and CFN (Wistar-derived) rats. Thresholds to PTZ seizures were measured after administering the convulsant either by the intraperitoneal or intravenous route. The data revealed an anticonvulsant action of morphine on both flurothyl and PTZ. Peak time for this effect on flurothyl seizures was 30 minutes after subcutaneous administration of the opiate, with the maximal anticonvulsant activity appearing at the 64-mg/kg dose. The increase in seizure threshold in S-D rats at this dose was 36% with flurothyl, 94% with intravenous PTZ and 352% with i.p. PTZ. Morphine had a less dramatic influence on raising the latter seizure threshold in the CFN than in the S-D strain. The graded dose-related anticonvulsant action is independent of the respiratory depression associated with morphine administration and appears to be a reflection of an altered central nervous system excitability produced by the narcotic in rats.


Action of anaphylaxis and histamine on isolated mammalian ventricles: contractile hyperactivation and changes of membrane potentials. The effects of anaphylaxis and histamine on the action potential and the isometric contraction of isolated guinea-pig papillary muscles have been investigated. The anaphylactic reaction was found to affect directly ventricular muscle fibers. The anaphylactic alterations of membrane and contraction parameters were very similar to effects of histamine and were not affected by pretreatment with reserpine. Isometric contraction developed typical features of contractile hyperactivation, characterized by a marked increase of peak force associated with shortening of time to peak of contraction and the appearance of oscillatory contractions and aftercontractions. Mechanical alternans and electrical alternans were also observed. Oscillatory contractions occurring during membrane depolarization were increased with prolongation of the action potential duration. After contractions developed after complete repolarization of the membrane and increased at higher stimulation rates. The anaphylactic reaction and histamine caused shortening of the action potential. Resting potential, overshoot and maximum rate of rise of action potential were not significantly changed. A common mechanism of contractile hyperactivation based on a multicompartment model of the intracellular Ca movements in discussed.


Influence of calcium concentration on the rate of onset of cardiac glycoside and aglycone inotropism. Isolated rabbit atria were employed to examine the rate of onset of inotropism of two glycosides (strophanthin and ouabain) and aglycones (acetylstrophanthidin and ouabagenin) in the presence of various concentrations of calcium (0.55, 1.1, 2.2, 4.4 and 8.8 mM). The rate of onset of glycoside-induced inotropism was found to be greatly influenced by the calcium concentration. The rate of onset was increased in both low and high calcium, with the minimum rate of onset at 1.1 or 2.2 mM calcium. In contrast, the rate of onset of aglycone-induced inotropism was not dependent on calcium between 0.55 and 4.4 mM calcium. The rate of onset of aglycone-induced inotropism was increased at 8.8 mM calcium. The results are interpreted by postulating that the digitalis inotropic receptor is located in a membrane-limited compartment to which aglycones may gain access via passive diffusion but to which glycosides gain access mainly via a (calcium-dependent) carrier mechanism.


A comparison of effects of SKF 525-A and procaine on excitation-contraction coupling in single crayfish muscle fibers. The effects of beta-diethylaminoethyldiphenylpropylacetate hydrochloride (SKF 525-A) on excitation-contraction coupling and Ca-dependent electrogenesis are compared to those of procaine. At pH 7.2, SKF 525-A and procaine occur essentially (greater that 97%) as a free base and as a cation, respectively. At this pH, SKF 525-A elicited tension development, blocked K-induced contractures and the K-induced repriming of caffeine contractions, potentiated caffeine-induced tensions, inhibited the procaine-induced spikes and twitches and, depending on the concentration, either potentiated (25-50 muM) or depressed (greater than 100 muM) the tensions associated with the graded membrane electrogenesis. At the same pH, procaine blocked the contractions elicited by SKF 525-A, by high K media, by the graded electrogenesis and by caffeine, and converted the graded membrane responses into all-or-none spikes. It is proposed that SKF 525-A as a free base 1) inhibits membrane Ca activation more effectively than it depresses K conductance and 2) is synergistic with caffeine in reducing the effectiveness of Ca sequestration by the sarcoplasmic reticulum. Procaine as a cationic molecule is thought to depress K activation more than Ca activation during depolarization and to block the release of Ca ions from the sarcoplasmic reticulum.


Mechanism of action of spironolactone on adrenocortical function in guinea pigs. Spironolactone administration (50 mg/kg/day for 3 days) to make guinea pigs decreased cortisol production by adrenal slices in vitro. Adrenal microsomal and mitochondrial cytochrome P-450 levels were also decreased after treatment with spironolactone. The decline in adrenal cytochrome P-450 content was accompanied by decreases in microsomal 21-hydroxylase and mitochondrial cholesterol side-chain cleavage and 11beta-hydroxylase activities. Activities of other adrenal enzymes, such as delta4-hydrogenase and NADPH-cytochrome c reductase, were unaffected by spironolactone treatment. Cortisone administration to guinea pigs failed to mimic the effects of spironolactone on adrenal function, which indicates specificity of spironolactone action and excludes inhibition of adrenocorticotropin secretion as a mode of action. Addition of spironolactone to isolated adrenal mitochondria or microsomes produced type I spectral changes with spectral dissociation constants similar to those for endogenous steroid substrates. Spironolactone, in vitro, inhibited 11beta- but not 21-hydroxylase activity. The results indicate that spironolactone administration diminishes the activity of adrenal mitochondrial as well as microsomal cytochrome P-450-containing enzymes, resulting in a fall in corticosteroid output.


Metabolism of prostaglandins A and E in the perfused rabbit lung and the effects of selected inhibitors. Hypothermia (4 degrees C) reversibly inhibits metabolism of prostaglandin A1 (PGA1) in the perfused rabbit lung and decreases the transit time of PGA1 through the lung. Co-perfusion of PGA1 (0.28 muM) and PGE1 (2.8 muM) resulted in 48% inhibition of PGA1 metabolism. Ouabain and phenoxybenzamine (10(-5) M) did not significantly affect PGA1 metabolism. We examined the effect of diphloretin phosphate (DPP; 6.0 mu/ml) on the metabolism of prostaglandin A1 (0.28-5.03 muM) and E1 (PGE1;0.28-11.56 muM). The metabolism of both prostaglandins appeared to be saturable processes and, in the case of PGE, the data conformed to Michaelis-Menten kinetics: the apparent Km (muM) and apparent Vmax (nmol/lung X min-1) in control lungs were 9.0 +/- 0.3 and 87.9 +/- 1.4, respectively, and in the DPP-treated lungs were 9.6 +/- 0.5 and 57.7 +/- 1.8. This suggests that DPP acts in a noncompetitive manner. The magnitude of inhibition of PGA1 and PGE1 metabolism (both at 0.28 muM) was linearly related to the DPP concentration, over the range of 0.06 to 25.0 mug/ml. The ID50 values of DPP inhibition of PGA1 and PGE1 metabolism were 2.2 and 8.4 mug/ml, respectively. Perfusion of PGA1 at 2.96 muM or higher concentrations caused reversible vasoconstriction which was significantly inhibited (P less than .05) by DPP (6.0 mug/ml) by an average of 77.2 +/- 5.8% (n = 7).


Analgesic nephropathy: renal distribution of acetaminophen and its conjugates. Acetaminophen (APAP) and its conjugates (APAP-conj) are the major metabolites of phenacetin. To study their significance in the pathogenesis of analgesic nephropathy, their concentrations in the renal parenchyma were determined in conjunction with clearance measurements in 15 dogs with inulin as a reference marker. Particular attention was given to interpretation of the mechanisms responsible for the concentrations generated within the papilla. For APAP, APAP-conj and inulin there is a significant corticomedullary gradient which is inversely related to the rate of urine flow. For inulin and APAP-conj, this gradient may be explained by their concentrations within the tubular fluid of the distal nephron. With concentration in the urine as a reference, the apparent volume of distribution of inulin within the papilla is not fixed, but varies with the rate of urine flow. Using several different types of comparison with inulin, we found that the results with APAP are consistent with its penetration by diffusion into the cellular compartment of the papilla. Dehydration leads to maximal concentrations of APAP in the urine as well as in the tubular fluid and the cells of the distal nephron. This is consistent with the kinetics of diffusion.


Tissue distribution of levo-methadone in nonpregnant and pregnant female and male mice: effect of SKF 525-A 1,2. Male, nonpregnant and pregnant female (15-17 gestational days) mice were injected i.p. with saline or SKF 525-A (50 mg/kg) and 1 hour later with levo-3H-1-methadone (205 mug/kg; 0.8 and 5 mg/kg). Levels of free methadone were examined in some or all of the following tissues: brain, plasma, liver, lung, spleen, kidney, heart, eye, placenta, amniotic fluid, whole fetus, fetal brain and liver. In saline controls, the methadone concentrations in several adult tissues, whole fetuses, fetal brain and liver reached peak levels at 15 minutes and were negligible at 24 hours. Tissue levels of methadone increased in a dose-related manner; however, the brain/plasma concentration ratios with the three doses were almost unity at 15 minutes, 1 hour and 3 hours. Among adult tissues with high concentrations were the lung, liver, kidney and spleen; the brain in contrast contained very low concentrations. No notable differences were detected in the tissue levels of methadone in males and nonpregnant females; however, in pregnant mice significantly higher levels were observed in the lung and the liver. Fetal brain, liver and whole fetus concentrations were approximately similar. At 15 minutes, the fetal brain contained about 3 times more methadone than the maternal brain and the difference increased at subsequent times. Nonpregnant females excreted somewhat larger amounts of 3H in the urine than did pregnant females. SKF 525-A markedly enhanced and prolonged the concentrations of methadone in all the adult and the fetal tissues and lowered urinary excretion of total radioactivity in nonpregnant and pregnant females. Marked increases in tissue radioactivity after SKF 525-A might be due to a combination of effects involving inhibition of drug metabolism, altered tissue distribution and lower urinary excretion.


Effect of 6-hydroxydopamine and 5,6-dihydroxytryptamine on the response of the coaxially stimulated guinea-pig ileum to morphine. Studies were conducted to determine the role of norepinephrine and 5-hydroxytryptamine in the action of morphine in the coaxially stimulated guinea-pig ileum. 6-hydroxydopamine produced supersensitivity to norepinephrine and decreased the levels of norepinephrine in the ileum. 6-Hydroxydopamine did not interfere with the acute effects of morphine but did interfere with the degree of tolerance developed to morphine, which is in contrast to reported results of the effect of 6-hydroxydopamine on the analgesic response to morphine. No evidence was found that 5,6-dihydroxytryptamine altered the acute or chronic response of the ileum to morphine. Again this is in contrast to results for the analgesic receptor where 5,6-dihydroxytryptamine has been reported to inhibit the development of tolerance to morphine. Thus, the role of the biogenic amines in the action of morphine in the ileum appears to differ from their reported role in the action of morphine in the central nervous system.


Effects of neonatal or maternal methadone administration on ornithine decarboxylase activity in brain and heart of developing rats. Methadone was administered daily to pregnant or nursing rats, or directly to neonates, and the effects on brain and heart weights and ornithine decarboxylase (ODC) activities were determined during postnatal development. Exposure to methadone in the postnatal period either directly or via the mother resulted in delays in maturational decreases in brain ODC accompanied by deficits in brain weight. Prenatal exposure alone had less effect on brain weight or ODC but appeared to enhance the effect of subsequent methadone exposure during the postnatal period. In the heart, direct methadone exposure or prenatal plus postnatal maternal administration led to a pattern of altered ODC activity consistent with delayed development, accompanied by heart weight deficits. The disturbance of heart ODC development after purely prenatal or purely postnatal maternal exposures differed from that obtained after direct administration to the neonate. These data show that exposure to methadone during fetal and/or neonatal life produces alterations in polyamine metabolism which may result in abnormal organ development. The type of change is dependent upon the period and route of exposure and may reflect both direct effects on the pup and indirect effect from drug-induced alterations in maternal metabolism or behavior.


The deveolopment of a radioimmunoassy for detection of cocaine metabolites. This paper describes the production of antibenzoylecgonine (BE) serum in rabbits and sheep from an ecgonine-sheep gamma globulin conjugate. With the use of this antiserum a radioimmunoassay was developed capable of detecting 5 to 10 ng of benzoylecgonine, a major cocaine metabolite in human urine. The antibody recognized ecgonine approximately 1/2, benzoylnorecgonine 1/10, cocaine, 1/5, and norcocaine and ecgonine methyl ester less than 1/50 as much as benzoylecgonine. The radioimmunoassay has been utilized in the measurement of benzoylecgonine levels in human urines and in organs and biological fluids of rabbits and rats. Qualitative results were compared with the Enzyme Multiplied Immunoassay Technique and thin-layer chromatography and found to be in good agreement. The technique is the most sensitive one available for monitoring cocaine ingestion by man and allows for specific determination of benzoylecgonine directly in urine without extraction and/or derivatization. Although ecgonine-sheep gamma globulin was used as the immunogen, the total antibody produced by both species was more reactive with respect to BE. The greater reactivity to BE suggests a possible conversion of a significant portion of the conjugated ecgonine in vivo to compound(s) conformationally more closely related to BE against which the major portion of the total antibody subsequently elicited was directed.


Mode of action of trichloroethylene on squid axon membranes. The mode of action of trichloroethylene on electrical properties of squid giant axons has been studied by means of voltage clamp techniques. Trichloroethylene decreased the resting membrane potential in a manner dependent upon the concentration, the depolarization by 50% saturated trichloroethylene attaining 28.4 and 32.7% of the initial value at 20 and 10 degrees C, respectively. Leakage conductance was decreased to 34.6% of the control by 30% saturated trichloroethylene at 10-12 degrees C. It appears that the trichloroethylene-induced depolarization is at least in part due to a decrease in resting potassium permeability. Both peak transient and steady-state conductance increases were suppressec by trichloroethylene, and the curve relating the steady-state conductance to the membrane potential was shifted in the depolarizing direction while the peak transient conductance curve was not appreciably shifted. The reversal potential for the peak transient current was greatly shifted by trichloroethylene in the direction of hyperpolarization in a manner dependent on the concentration, the maximum shift amounting to 25 mV at 10 degrees C. This effect was less pronounced at 20 degrees C. The shift in the reversal potential is mostly due to a decrease in selectivity of the peak transient channel and partly due to an accumulation of sodium ions inside. Analyes of dose-response relation in suppressing peak transient and steady-state conductances show that trichloroethylene interacts with receptor on a one-to-one stoichiometric basis. Steady-state sodium inactivation curve was shifted by trichloroethylene in the direction of hyperpolarization. All of these effects were partially reversed after washing the axon with anesthetic-free media. The accumulation of sodium ions inside would be much more pronounced in small nerve fibers in the brain than in giant axon and, together with the observed decrease in the selectivity of peak transient channels, would play a significant role in general anesthesia.


Uptake and metabolism of nicotine by the isolated perfused rabbit lung. In order to investigate the possibility of pulmonary first-pass metabolism of nicotine inhaled in tobacco smoke, the absorption and disposition of 14C-nicotine were studied in an isolated perfused rabbit lung preparation after nicotine administration directly into the perfusing blood and tobacco smoke administration via in the inspired tracheal air. After administration into the perfusing medium, the rate of nicotine metabolism was first-order and dose-independent at the two doses studies (0.1 and 1.0 mg) but lung metabolic clearance was quite low (3 ml/min) relative to whole body clearance (140 ml/min) measured by administering 14C-nicotine to intact rabbits. Accumulation of nicotine by lung was not extensive (13-23% of the dose administered). After administration of tobacco smoke from 14C-nicotine-spiked cigarettes, absorption of nicotine was rapid but the rate of metabolism was markedly reduced compared to the studies in which drug was administered in the perfusing medium. This reduction in the rate of metabolism was apparently caused by some component of tobacco smoke but was shown to be unrelated to the level of carbon monoxide in the perfusate. The slow clearance of nicotine by rabbit lung (which is further reduced after smoke administration) compared to a high pulmonary blood flow rate makes unlikely the possibility of significant first-pass lung metabolism in smokers.


The effects of physostigmine on cholinesterase activity, storage and release of acetylcholine in the isolated chicken heart. Total activity of the cholinesterases (ChE) and the concentration and output of acetylcholine (ACh) were measured in isolated chicken hearts. The ACh concentration of the right ventricle was as high as that of the total heart (approximately 7 nmol/g). The ChE activity and its kinetic parameters did not differ from those of other vertebrates. In the absence of physostigmine, stimulation of both vagus nerves (20 Hz, 5 minutes) caused an output of ACh and a decrease in rate (-90% of control) and amplitude (-74%) of the ventricular contraction. Physostigmine (10(-7) M) inhibited the ChE by 87%, caused a small reduction of the ACh concentration (P = .05) and more than doubled the ACh output in response to vagal stimulation. In contrast, 10(-6) M physostigmine increased significantly the ACh concentration by about 40% within 5 minutes; the output was almost 3-fold higher than that in the absence of physostigmine and the ChE was nearly completely inhibited (-96%); the output of ACh in the 5th minute of stimulation was not significantly lower than that in the 1st minute. Physostigmine, in a concentration of 10(-4) M, did not change the ACh content of the heart and was much less effective in elevating the ACh output than was a concentration of physostigmine of 10(-6) M. In conclusion, the high ACh output from isolated chicken hearts evoked by preganglionic nerve stimulation was at least partially due to the pronounced innervation of the avian ventricles. Inhibition of the ChE by 96% failed to cause ganglionic transmission block. The formation of surplus ACh required higher physostigmine concentrations (10(-6) M) than the inhibition of the external ChE (protection of ACh released). High physostigmine concentrations (greater than 10(-6) M) counteracted the formation of surplus ACh.


Maturation of renal organic acid transport in vivo: substrate stimulation by penicillin. These experiments were designed to demonstrate that pretreatment of newborn dogs with penicillin will enhance maturation of the renal organic anion transport system in vivo. Littermate pups were injected with procaine penicillin G (300,000 I.U./kg b.i.d. for 3 days) or saline before 2 weeks of age. Animals were surgically prepared on day 16 or 17. Transport of p-aminhippurate (PAH), as an indicator of renal organic anion transport, was quantified by the following procedures: 1) disappearance of a bolus injection from the plasma, 2) renal extraction and 3) rate of secretion in steady-state clearance experiments. The renal handling of insulin was measured simultaneously in all procedures for comparison. Penicillin-treated animals excreted a single intravenous bolus of PAH more rapidly than control animals, with the T1/2 decreased and the constant of elimination (Ke) increased. The extraction of PAH by kidneys of penicillin-treated animals was 165% that of controls. Similarly, the tubular secretion of PAH was increased in treated pups. These data confirm that in newborn animals the renal handling of organic anions in vivo is enhanced by pretreatment with a substrate of the secretory system.