Gas-liquid chromatographic studies of reactions and structural relationships of steroids. V. Concurrent substitution in the pregnane side-chain and position II. Qualitative and quantitative effects of classical reactions on steroids observed by gas-liquid chromatography (GLC) under standardized conditions, including the double internal standard technique, are reported. Simple procedures applicable to nanogram amounts of reactants are described. Reactions studied include the conversion of keto groups to hydroxyl groups by NaBH4, and the removal of the pregnane side-chain with NaBiO3. GLC chromatograms readily provide information on effects on functional groups at positions 3, 11, 17, 20, and 21 and the retention times of many steroids unavailable from commercial sources. GLC data analysis provides relationships between steroid structure and retention time from which methods for the computation of retention times and steroid identification are designed. The accuracy of these methods is demonstrated.


Liquid chromatography of nucleic acid components and their analogues on hydroxyethyl methacrylate gels. Spheron hydroxyethyl methacrylate gels are advantageous sorbents for the high-performance liquid chromatography of various nucleic acid components and their analogues. In aqueous media these compounds are reversible sorbed on the surface of the gel. Differences in the sorption characteristics of particular derivatives enable good separations of even relatively complicated mixtures to be achieved.


Gas chromatography of methyl glycosides as their tri-methylsilyl ethers. The methanolysis and re-N-acetylation steps. Gas chromatographic procedures for the analysis of carbohydrates in glyco-proteins frequently include methanolysis and re-N-acetylation steps. The usual methanolysis conditions were found to result in almost complete conversion of the methanolic HCl into methyl chloride. A neutral solution of methyl chloride in methanol was found capable of releasing fucose, sialic acid, and a portion of the galactose from alpha 1-acid glycoprotein. During the re-N-acetylation of the amino sugars O-acetylation of the alditols commonly employed as internal standards occurs. Addition of the standards after the re-N-acetylation step avoided the problem. The complete procedure for the determination of both neutral and amino sugars has been simplified to involve only one transfer step prior to final gas chromatography.


Gas chromatographic separation of diastereoisomeric amino acid derivatives on glass capillaries. THE USE OF PENTAFLUOROPROPIONYL-AMINO ACID (+)-3-METHYL-2-BUTYL ESTERS. The separation of diastereoisomeric pentafluoropropionyl-D, L-amino acid (+)-3-methyl-2-butyl esters, including those derived from histidine, arginine and tryptophan, is achieved on glass capillaries. Separation factors of between 1.03 and 1.09 are observed for the derivatives of protein amino acids. The gas chromatographic separation of a mixture of common amino acids usually takes less than 1 h.


Determination of (+)-(3R), (4S)-3-[(4methoxyphenoxy)methyl]-1-methyl-4-phenylpiperidine hydrochloride (FG 4963) in biological fluids using competition for adsorption to glass. A procedure has been developed for the gas chromatographic determination of a structurally new 5HT-uptake inhibitor with antidepressant properties (FG 4963) in plasma and urine. The method involves an extraction from alkaline solution with n-pentane, and a quantitative determination by gas chromatography using an internal standard and a nitrogen-sensitive detector. The binding of FG 4963 to glass during storage and evaporation necessitates the addition of a structurally similar compound to the vials used for collection of the blood and urine, in order to compete for the binding sites of the glass. The method is suitable for pharmacokinetic and clinical studies, the sensitivity being ca. 5 ng/ml in plasma and 1 ng/ml in urine and the precision being 10-15% for concentrations greater than 10 ng/ml.


Determination of papaverine in blood samples by gas-liquid chromatography and mass fragmentography. The measurement of papaverine in blood samples by using either a glass capillary column with a flame-ionization detector or a packed column with mass fragmentographic detection is described. The two methods permit the determination of the normal range of concentrations of papaverine in blood (2-500 ng/ml). Owing to its high specificity, mass fragmentography is greatly superior to capillary chromatography, which is sometimes subject to interferences by solvent impurities.


Determination of debrisoquine and its 4-hydroxy metabolite in biological fluids by gas chromatography with flame-ionization and nitrogen-selective detection. Specific methods have been devised for the simultaneous determination of the guanidino-type antihypertensive agent debrisoquine and its 4-hydroxy metabolite in human urine, involving in situ derivatisation with acetylacetone, extraction of the resulting pyrimidines, and gas chromatography using a flame-ionisation detector or a nitrogen-specific detector. Using the latter, a similar procedure was also developed to measure debrisoquine in human plasma and whole blood following prior extraction at pH 13.5 with chloroform. Concentrations down to 3 ng/ml can be measured accurately using a 1.0-ml sample. The methods were applied to the analysis of samples collected after a single 20-mg oral dose of debrisoquine hemisulphate.


A nitrosamide-specific detector for use with high-pressure liquid chromatography. A highly specific automated method for identification of nitrosamides has been developed for use in conjuction with reversed-phase high-pressure liquid chromatography. The method is based on the well-known Griess reagent, and is capable of sensitivities of 0.5 nmoles of injected nitrosamide in most cases. The method may be used for analysis of nitrite, nitrosamides, nitrosocarbamates, and alkylnitrites.


Rapid method for the simultaneous determination of 1,4-dioxan and its major metabolite, beta-hydroxyethoxyacetic acid, concentrations in plasma and urine. 1,4-Dioxan and its principle metabolite, beta-hydroxyethoxyacetic acid (HEAA), are determined by gas chromatography-mass spectrometry (GC-MS) on a 3% OV-17 column using selected ion monitoring, following the methylation of HEAA directly in plasma or urine without extraction. The recoveries of dioxan from plasma and urine are 98 and 94%, respectively, and the recoveries of HEAA from plasma and urine are 86 and 94%, respectively. The detection limits of 1,4-dioxan in plasma and urine are 0.07 ppm, and the detection limits of HEAA in plasma and urine are 0.5 and 0.1 ppm, respectively. Separate simultaneous measurements of 1,4-dioxan and HEAA methyl ester concentrations in urine and plasma are obtained after the methylation via GC-MS without additional preparation of the samples.


Gas-liquid chromatography of methylpentynol carbamate and its metabolite 3-methylpentyne-3,4-diol. Procedures are described for the determination of methylpentynol carbamate in serum, either by injection into the chromatograph of diluted serum or extraction of the drug into chloroform and injection of an aliquot of the concentrated organic phase; a 4% CDMS column is used. Similar assays for measuring the metabolite 3-methylpentyne-3,4-diol in urine are reported. The methods have been used for measuring methylpentynol carbamate and its metabolite in samples from rats and dogs.


Liquid chromatographic separation of bile acids. The recent revival in interest in the role of bile acids in biological systems has emphasised the importance of analysing individual bile acids for the presence of closely related impurities. An assessment of the value of modern, high-performance liquid chromatography for this application has shown that mixtures of underivatised bile acids may be resolved by reversed-phase chromatography. Separation of isomeric acids and those differing in the extent of hydroxyl substitution is possible by this approach. Mixtures of amino acid conjugates of bile acids may also be resolved by this method. The use of an ultraviolet absorbance detector, operating at a wavelength in the region of 210 nm, results in a detection limit in the order of 50 ng.


Thin-layer chromatographic classification of antibiotics exhibiting antitumor properties. A classification system for 151 antibiotics exhibiting antitumor properties using thin layer chromatography (TLC) and bioautography was developed. TLC classification is based on mobility of the compounds in a solvent system using a certain adsorbent, rather than on misleading RF values. The solvent systems and conditions used are presented.


Use of silylating agents for the identification of hydroxylated steroids by gas chromatography and gas chromatography-mass spectrometry. Discrimination between phenolic and alcoholic hydroxyl groups. A phenolic trimethylsilyl (TMS) group was selectively exchanged for a dimethylalkylsilyl (DMAS) group on a gas chromatographic column by use of sandwich injection technique with DMAS-imidazole, and a TMS ether derivative of a phenolic steroid was converted into a DMAS ether or a mixed TMS and DMAS ether derivative with over 95% recovery. The selective exchange reaction seemed to be caused by the difference in lability between the ethereal TMS linkages to phenolic and alcoholic hydroxyl groups. This selectivity was found to be useful for discriminating gas chromatographically between the phenolic and alcoholic hydroxyl groups in steroids.


Determination of the configurations of lactic and glyceric acids from human serum and urine by capillary gas-liquid chromatography. The separation of the enantiomers of lactic and glyceric acids can be achieved by capillary gas chromatography on SP-1000 using the corresponding O-acetylated methyl esters. The structures of the derivatives were proved by proton magnetic resonance spectroscopy and mass spectrometry. The method has been used for the determination of the absolute configuration of lactic and glyceric acids isolated from serum and urine from different patients.


Rapid chromatographic method to determine polyamines in urine and whole blood. A procedure is described for the rapid determination of putrascine, spermine and spermidine in ruine and whole blood. The samples are hydrolyzed with barium hydroxide and are neutralized with sulfuric acid. The polyamines are concentrated and separated from amino acids on a small bed of ion-exchange resin that then serves to load the samples on a two-channel, automated ion-exchange chromatography apparatus. As many as 100 samples can be analyzed in a 24-h period. The method has been shown to be applicable to the analysis of urine and whole blood samples, but further development is needed for application to serum samples.


Recommended method for the analysis of amino acids in biological materials. Fifty-five ninhydrin-positive compounds in physiological fluids were determined with a Hitachi Model KLA-5 amino acid analyzer by a two-column chromatographic procedure. Both columns were packed with Hitachi Custom 2618 ion-exchange resin. The total analysis time was 9.5 h. In this procedure, particularly glucosamine, mannosamine and galactosamine were separated completely from normal "protein" amino acids, and NG-monomethylarginine, NG, NG-dimethylarginine and NG,NG-dimethylarginine, which were present in the myelin basic protein of several species and excreted in human urine, were separated from other basic amino acids. The method is useful for various applications with biological materials.


Quantitative analysis of human serum cholesterol by thin-layer chromatographic spot test. A fast, inexpensive, simple method is described for the determination of the total cholesterol concentration in human serum. The cholesterols (free and esterified) are extracted from serum by a double extraction procedure, using isopropanol-water-10 N sodium hydroxide (250:125:10) and then n-octane. An aliquot of the octane extract is spotted on a thin-layer plate and the cholesterol in the spot is rendered visible using an aqueous phosphomolybdic acid staining solution and a heat treatment for the color development. The colored spot is scanned with a densitometer.


Micro-determination of plasma diphenylhydantoin by gas-liquid chromatography. A selective, sensitive and precise gas-liquid chromatographic method for the determination of diphenylhydantoin in micro samples of blood plasma is described. After a double extraction with chloroform containing an analogue of diphenylhydantoin as an internal standard, the drug and standard are N,N-dimethylated in alkaline aqueous solution with methyl iodide followed by extraction into acetone. The methylated derivatives are separated gas chromatographically and measured using a flame-ionization detector. The lowest concentration of diphenylhydantoin in plasma which can be measured in a 100 mul sample is 1 mug/ml, which is well below the normal therapeutic concentration of 10-20 mug/ml in plasma. The methylated derivatives of diphenylhydantoin and the internal standard have been identified by their proton magnetic resonance spectra and mass spectra.


Rapid trace analysis of barbiturates in blood and saliva by high-pressure liquid chromatography. The performances of a number of liquid--solid systems, consisting of mixtures of water and methanol as liquid phase and methyl silica as solid phase, were investigated with respect to their use in the separation of barbiturates by high-pressure liquid chromatography (HPLC). Phase system selectivities and column efficiencies were determined. The results were applied to the development of a rapid method for the determination of trace amounts of barbiturates in blood. The first step in the analysis, the extraction of barbiturates from blood, was also investigated and good recoveries were achieved. The extracts were analyzed by HPLC using ultraviolet detection at 220 nm. A low detection limit and high precision were obtained; An amount of 5 ng hexobarbital, for example, can be determined with a precision of +/-15% and 5 mug with a precision of +/-0.3%. The time course of the concentration of hexobarbital in the serum and saliva of man after an oral administration of 400 mg is demonstrated.


The determination of allopurinol and oxipurinol in human plasma and urine. A method is described for allopurinol and oxipurinol assay within human plasma and urine in the range expected during therapy. The method is based on high-performance ion-exchange chromatography following an efficient sample purification step using Chelex-100 resin in the Cu2+-form. Linear calibration curves are produced for allopurinol over the range 0.05-10 mumole/1 (0.068-1.36 mug/ml) in plasma and 0.005-1 mmole/1 (0.68-136 mug/ml) in urine and for oxipurinol 0.5-100 mumole/1 (0.076-15.2 mug/ml) in plasma and 0.1-2 mmole/1 (15.2-304 mug/ml) in urine.


The nature of the defect in a salt-wasting disorder in Jews of Iran. Studies in 8 families of Iranian Jews revealed 12 patients with selective aldosterone deficiency due to a biosynthetic defect. There was a marked range in clinical severity which varied from acute salt-wasting crisis in infancy to an asymptomatic state in adults detectable only by biochemical screening. Manifestations of intermediate degrees of severity included unexplained short stature and postural hypotension. This clinical variability in the manifestations of aldosterone deficiency was not due entirely to quantitative differences in hormone secretion but also to a changing pattern of requirement throughout life in which deficiency during the first year of life had grave consequences while a similar degree of deficiency in the adult was well-tolerated, suggesting that the hormone was no longer essential. Most families came from a relatively isolated community in Isfahan with a high incidence of consanguinity and three were related. Aldosterone deficiency was due to an inborn error involving the terminal portion of the biosynthetic pathway and characterized by marked overproduction of glomerulosa zone 18-hydroxycorticosterone relative to aldosterone. The best diagnostic index was the excretory ratio of the major urinary metabolites of these steroids. This ratio, normally less than 3.0, was frequently greater than 100 in untreated patients with this defect. Plasma aldosterone was not a reliable index of the disorder since some patients achieved normal levels but at the expense of marked elevation in plasma renin activity and overproduction of precursors.


Renin reactivity in plasma of patients with normal renin and low renin essential hypertension. Plasma renin reactivity (PRR) is the rate of angiotensin generation in vitro after addition of exogenous renin to plasma. To evaluate the hypothesis that suppressed plasma renin activity (PRA) in patients with low renin essential hypertension may be related to an alteration of the kinetics of the in vitro renin reaction, PRR was compared in plasma of patients with low renin and normal renin essential hypertension. Prostaglandin A (PGA) inhibits renin, and PGA was also measured to determine if suppressed PRA may be related to increased PGA. Low renin and normal renin hypertension were defined by comparing PRA responses of 30 hypertensive patients and 16 matched control subjects to upright posture and furosemide (80 mg p.o.). Nine of 30 patients had low PRA. Compared to that in plasma of patients with normal renin hypertension, PRR was suppressed (P less than 0.005) during 30, 60, and 180 min incubations in the low renin patients. Overall, in the hypertensive patients, there was a significant positive correlation (r= +0.58; P less than 0.01) between PRR and the PRA response to furosemide. PGA in patients with low renin hypertension (0.86 ng/ml+/-0.06 SE) was less (P less than 0.05) than that in patients with normal renin hypertension (1.10 ng/ml+/-0.07) SE) and control subjects (1.18 ng/ml+/-0.10 SE); PGA of normal renin patients and control subjects did not differ (P less than 0.1). These results suggest that an alteration of the kinetics of the renin reaction may contribute to the apparent renin suppression in patients with low renin hypertension. Hypertensive patients with suppressed PRA also have low PGA.


Serum thyrotropin and thyroid hormone levels in humans receiving chronic potassium iodide. Serum thyroxine (T4), triiodothyronine (T3) and thyrotropin (TSH) concentrations were measured in 13 patients with chronic obstructive pulmonary disease receiving saturated solution of potassium iodide (SSKI). All had a low serum T4 and a high serum TSH concentration. However, serum T3 levels were normal in eight. Recovery of normal thyroid function was observed in each of the seven patients in whom the iodide was discontinued. The same hormones were measured in four normal subjects who received 30 drops of SSKI daily for 11 weeks. An increase in serum TSH levels was preceded by a fall in serum concentrations of T4 and to some extent, T3. Upon SSKI withdrawal  subsequent increases in the serum concentrations of both thyroid hormones, but particularly T3, resulted in the return of serum TSH to baseline levels. None of the subjects developed clinical hypothyroidism. It is not apparent why the normal subjects did not exhibit clinical or laboratory evidence of hypothyroidism while the patients with chronic pulmonary disease did. A younger age and the shorter duration of iodide administration in the normal subjects may have played a role.


Growth hormone, glucagon, and insulin response to depression of plasma free fatty acids and the effect of glucose infusion. It has previously been shown that nicotinic acid (NA)-induced depression of free fatty acids (FFA) stimulates the secretion of GH and glucagon. To evaluate this hormonal response further, we studied the influence of different doses of glucose administered by continuous iv infusion on the GH and glucagon increase during NA-induced FFA depression. In ten male non-obese volunteers, FFA depression by the infusion of NA (2.3 g over a period of 210 min) resulted in a late rise (from 150 min on) of GH (From 1.1 to 25.9 ng/ml) and an early increase (from 30 min on) of glucagon (from 71.7 to 138.2 pg/ml). When glucose was infused (approximately 60, 120 and 180 g, respectively, over a period of 270 min) during NA-induced FFA depression, the GH rise was reduced and delayed in relation to the amount of glucose infused, but could not be completely abolished (maximal GH concentration during the three NA-plus-glucose infusions: 16.5, 8.0 and 6.1 ng/ml, respectively). The glucagon rise was entirely reversed by the high glucose dose. Insulin did not rise during NA infusion alone. Its secretion in response to glucose infusion was not significantly influenced by FFA depression. Thus, during NA-induced FFA depression the secretion of two lipolytic hormones--GH and glucagon--is stimulated while the secretion of the lipogenetic hormone insulin remains low. Glucose has an inhibitory effect on the GH and glucagon response which, however, is different for each of the hormones.


Studies on human sexual development. IV. Fetal pituitary and serum, and amniotic fluid concentrations of prolactin. Prolactin concentrations were measured in 161 amniotic fluid specimens from 8-40 weeks fetal age and the levels compared with those observed in 45 fetal and neonatal cord sera and in 42 fetal pituitary specimens. Amniotic fluid prolactin levels rose steeply between 12-16 weeks gestation, and then declined to term; the calculated total amniotic fluid content of prolactin showed a similar pattern, but the peak was later, at about 26 weeks gestation. Amniotic fluid concentrations consistently exceeded fetal serum prolactin levels, even during the last trimester, when fetal serum and pituitary levels were highest. The data are compatible with a fetal origin for amniotic fluid prolactin, but only if one assumes that flux of prolactin out of amniotic fluid compartment is negligible, that the fetal kidney in mid-pregnancy clears prolactin at a rate virtually equal to the glomerular filtration rate, and the fetal pituitary shows secretion characteristics quite different from those of the adult gland.


Glucagon and catecholamine secretion during hypoglycemia in normal and diabetic man. To examine the role of catecholamines in glucopenia-induced glucagon secretion, urinary epinephrine and norepinephrine and plasma immunoreactive glucagon (IRG) were measured during insulin-induced hypoglycemia in normal and insulin-dependent diabetic-man. Despite equivalent levels of hypoglycemia the mean plasma IRG increment in diabetes was only 15% of normals. The increases in epinephrine and norepinephrine were comparable in diabetics and normals; thus, the blunted response in plasma IRG to the stimulus of low blood sugar in diabetics cannot be explained by a generalized defect in catecholamine secretion. It is suggested that an alpha-cell glucoreceptor defect may account for the abnormal response to glucopenia in diabetics. To evaluate the possibility that impaired sensitivity to circulating catecholamines could explain the alpha cell dysfunction in diabetics, exogenous epinephrine was infused in normals and insulin-dependent diabetics. Elevated plasma IRG during epinephrine infusion was observed in only 50% of normals. The diabetics were hyperresponsive; mean increment in plasma IRG 3 times that of normals. The data demonstrate enhanced rather than impaired sensitivity to catecholamines in diabetes mellitus.


Effect of dopamine on plasma growth hormone and prolactin levels in normal and acromegalic subjects. In contrast with other dopaminergic drugs (L-dopa, apomorphine or bromocriptine) a 280 mug/min dose of dopamine infused for 120 min failed to induce an increase in plasma GH in 9 normal subjects. During dopamine infusion, no significant change in the GH response to arginine was also noted, whereas prolactin displayed a significant fall. In 15 acromegalic patients, on the other hand, the drug caused a marked fall in both GH (mean+/-SE; 71.1%+/-5.6) and prolactin (mean+/-SE; 67.6%+/-4.0) followed by a distinct rebound after the end of the test. There was a very close relation (P less than 0.001) between the maximum per cent decrease in GH during dopamine and after 2.5 mg bromocriptine by mouth. Dopamine also inhibited the GH response to TRH (4 patients). Since dopamine does not readily cross the blood-brain barrier, these results suggest that the stimulating effect of dopaminergic drugs on GH secretion in the normal subject is exerted via the CNS, whereas in acromegaly there is a direct action on structures lying outside the blood-brain barrier, probably in the hypophysis. Dopaminergic inhibition of prolactin is primarily the result of action on the hypophysis, as well as on the hypothalamus, in both normal and acromegalic subjects.


Insulin-glucagon interaction in controlling splanchnic glucose production in normal man. The interaction of glucagon and insulin in controlling hepatic glucose production in man has been inferred from studies of immunoreactive glucagon and insulin. This study directly examines the interaction of glucagon and insulin in controlling net splanching glucose production (NSGP) in eight normal men. Glucagon was infused iv at 5 ng/kg/min for 15 min and resultant arterial glucagon levels (1.3 X 10(-10) M) did not exceed the physiologic portal range. In four normal men NSGP increased 2.3-fold by 5 min and remained elevated for 15 min. There was no change in arterial insulin concentration. To study the effect of exogenous insulin on this glucagon-induced increase in NSGP, insulin was infused at 10 mU/kg/min in four normal men to achieve arterial immunoreactive insulin concentrations of 1500 muU/ml (1 X 10(-8) M). Blood glucose was stabilized by glucose infusions. During insulin and glucose administration, NSGP was suppressed and net splanchnic glucose uptake occurred. After 40 min of insulin and glucose pretreatment, a 5 ng/kg/min glucagon infusion resulted in no increase in NSGP (arterial insulin: glucagon molar ratio of approximately 100). In two subjects the glucagon infusion rate was then increased to 15 ng/kg/min (arterial insulin: glucagon molar ratio of approximately 33), resulting in stimulation of NSGP. These studies provide evidence that insulin in high concentration can suppress glucagon-stimulated NSGP in normal man.


A variant of iodotyrosine-dehalogenase deficiency. Three siblings (products of consanguineous marriage) affected with iodotyrosine-dehalogenase deficiency (presumed homozygotes) were found to have low thyroxine and large multinodular goiters, but none was mentally retarded. Iodide therapy corrected the serum T4 and thyroidal iodide uptake and discharge curve. The goiters shrank with iodide treatment. The subjects demonstrated significant ability to deiodinate intravenously injected L-mono-iodotyrosine (MIT) but not L-diiodotyrosine (DIT); 9.9% and 80.0% of an injected dose of 125I-MIT and 125I-DIT appeared unchanged in the urine 4 h, respectively. The data in presumed heterozygote subjects (both parents and two other siblings) were intermediate between controls and affected subjects. Thyroidal dehalogenase activity was measured in one of the affected subjects in vitro. The tissue showed greater ability to deiodinate MIT than DIT, but both activities were much lower than that of control tissue. The disease appears to be transmitted in an autosomal recessive fashion. The MIT-dehalogenase activity demonstrable in the affected individuals may explain the mild phenotype, in that MIT leaking from the goiter can be deiodinated to a significance degree and the liberated iodide reutilized.


A case of idiopathic hypoparathyroidism and dietary vitamin D deficiency: the requirement for calcium and vitamin D for bone, but not renal responsiveness to PTH. A patient with concurrent idiopathic hypoparathyroidism and dietary vitamin D deficiency was studied. Acute renal responsiveness to PTH was demonstrated by immediate increases in urinary cyclic AMP and phosphorus excretion. An impaired bone response to sustained PTH administration was demonstrated by absence of significant increases in serum calcium or urine hydroxyproline during 3 days of PTH administration. Skeletal responsiveness was restored either by raising the initial serum calcium with constant calcium infusion or by raising serum 25-OH-D levels to normal by administration of 1,000 units vitamin D daily. These results extend to the human, animal observations which suggest that vitamin D is required for the skeletal but not for the renal actions of parathyroid hormone.


Steady state hormonal secretion in traumatic quadriplegia. Physiologically complete cervical spinal cord transection results in motor and sensory quadriplegia and interruption of the sympathetic neural pathways; this condition leads to metabolic deficiencies suggestive of abnormal endocrine function. An investigation of the non-stimulated secretion of some of the hormones influencing metabolism was undertaken by evaluating thyroxine, iodothyronine binding index, testosterone, growth hormone, calcitonin, and parathyroid hormone in venous blood of fasting healthy subjects and quadriplegic patients. The effect of the duration of the paralysis was examined by repeating the evaluations at different periods after onset. The results show that 1) thyroxine was low for 2 months after onset in 21 patients and normal thereafter in 53 patients, 2) testosterone was low throughout the study in 62 patients; the decrease is greatest during the first 2 months, 3) growth hormone was often increased in 46 patients for 8 months after onset, and nearly normal afterward in 25 patients, 4) calcitonin was normal in 22 patients throughout the study, and 5) parathyroid hormone was normal in relation to normal serum calcium as early as 6 days after onset in 79 out of 83 patients. These data do not preclude a parathyroid hormone increase at onset or alterations in the patterns of circadian secretion and in the responses to specific stimulation for the hormones evaluated. Therefore, it may be concluded only that the steady state secretion of these hormones is not altered by traumatic quadriplegia per se, but is temporarily modified by the original insult to the nervous system, and by changes in life pattern and the heavy sedation that follows. The results suggest that the minor endocrin changes occurring in quadriplegic patients during the early period of paralysis will be rapidly overcome by rehabilitation to an active life pattern.


Failure of papaverine to alter L-dopa-influenced GH and PRL secretion. Papaverine, 150 mg BID for 2 weeks, a dose which produced marked clinical impairment in Parkinsonian patients taking L-Dopa, failed to alter L-Dopa-stimulated GH secretion or L-Dopa inhibited PRL secretion in 6 normal volunteers. Failure to demonstrate an inhibitory effect of papaverine on dopaminergic hypothalamic-pituitary systems, despite its inhibition of striatal dopaminergic pathways, may imply qualitative or quantitative functional differences between hypothalamic and striatal dopaminergic systems.


The metabolism of [6-3H]1alpha, hydroxycholecalciferol to [6-3H]1alpha,25-dihydroxycholecalciferol in a patient with renal insufficiency. To evaluate whether 1alpha-hydroxycholecalciferol is metabolized to 1alpha,25-dihydroxycholecalciferol in man, [6-3H]1alpha-hydroxycholecalciferol was given intravenously to a patient with renal failure who was maintained daily on 100,000 IU vitamin D and calcium supplements. Using Sephadex LH-20 and high-pressure liquid chromatography, it was clearly demonstrated that 1alpha-hydroxycholecalciferol rapidly disappears from the blood and is metabolized to 1alpha,25-dihydroxycholecalciferol.


Transient appearance of a provocative growth hormone response to L-dopa following incomplete adenomectomy in an acromegalic patient. A 33-year female patient with active acromegaly and hyperthyroidism was examined before and after incomplete removal of a pituitary adenoma. Before adenomectomy the mean basal plasma GH level was 786+/-189 ng/ml. After surgery this value decreased to 251+/-22 ng/ml. Before surgery L-dopa decreased the plasma GH levels, but after adenomectomy normal GH responses were transiently observed to L-dopa. At 10 months after incomplete surgery the GH response to L-dopa became abnormal again despite a lower GH concentration. These findings suggest that the abnormal GH response to L-dopa may be due to a short-loop negative feedback system which was reset by an elevated GH level.


Effect of acute ammonia intoxication on cerebral metabolism in rats with portacaval shunts. Rats were made chronically hyperammonemic by portal-systemic shunting and, 8 wk later, were subjected to acute ammonia intoxication by the intraperitoneal injection of 5.2 mmol/kg of ammonium acetate. In free-ranging animals, ammonia treatment induced a brief period of precoma (10-15 min) that progressed into deep, anesthetic coma lasting for several hours and was associated with a high mortality. In paralyzed, artificially ventilated animals that were lightly anesthetized with nitrous oxide, acute ammonia intoxication caused major disturbances of cerebral carbohydrate, amino acid, and energy metabolism that correlated in time with the change in functional state. At 10 min after injection (precoma), the concentrations of most glycolytic intermediates were increased, as was the lactate/pyruvate ratio. Citrate declined, despite a twofold rise in pyruvate, suggesting that the conversion of pyruvate to citrate had been impaired. Concentrations of phosphocreatine, and of the putative neurotransmitters, glutamate and aspartate, declined during precoma, but the concentrations of the adenine nucleotides in the cerebral hemispheres, cerebellum, and brain stem remained within normal limits. At 60 min after injection (coma), ATP declined in all regions of brain; the reduction in total high-energy phosphates was most notable in the brain stem. The findings indicate that cerebral dysfunction in chronic, relapsing ammonia intoxication is not due to primary energy failure. Rather, it is suggested that ammonia-induced depletion of glutamic and aspartic acids, and inhibition of the malate-asparate hydrogen shuttle are the dominant neurochemical lesions.


Irreversible bronchial goblet cell metaplasia in hamsters with elastase-induced panacinar emphysema. A single intratracheal instillation of pancreatic elastase in hamsters induces a lesion resembling human panacinar emphysema. This paper reports the occurrence of irreversible goblet cell metaplasia in the bronchial epithelium of hamsters similarly exposed to elastase. The goblet cell change was dose related; a dose of 0.1 mg/100 g body wt or less at 16 days, produced slight or moderate goblet cell metaplasia in fewer than half the animals, whereas 84% of animals treated with a dose between 0.2 and 0.5 mg/100 g body wt developed goblet cell metaplastic lesions, more than half of which were considered to be severe. The percentage of goblet cells in the epithelium of elastase-treated hamsters (32.5) was significantly higher (P less than 0.005) than that of unexposed (12.2) and saline-exposed controls (18.7). All hamsters examined 6 and 12 mo after elastase treatment showed the lesion. The pathogenesis of the changes is unclear but the possibility is raised that the bronchial changes may be due to disturbance of an endogenous protease-antiprotease system. The findings suggest the hypothesis that, under appropriate circumstances, a single pulmonary insult in man could lead to a permanent lung injury demonstrating the anatomic lesions of both chronic bronchitis and panacinar emphysema.


Binding of collagen alpha1 chains to human platelets. We previously reported that purified alpha1 chains of type 1 chick skin collagen induce platelet aggregation. We now describe immunological and biochemical evidence that the peptide binds to intact platelets as an early event in the induction of platelet aggregation and the release reaction. Antibody against alpha1 (I) was obtained by immunizing rabbits with complete Freund's adjuvant mixed with purified alpha1. Immunofluorescence studies showed that alpha1(I)-treated platelets exhibited strong immunofluorescence. The intensity of fluorescence was markedly decreased by the pretreatment of platelets with alpha1-CB5 and glucosylgalactosylhydroxylysine. Dose-response curves of platelet aggregation induced by alpha1 and the binding of alpha1 by washed intact platelets are correlated. The biochemical studies showed that the binding of the alpha1 chain to washed intact platelets was platelet concentration and temperature dependent, and that it reached a maximum in 10 min. The process was reversible and specific, with an association constant of 1.7 muM. The inhibitor of alpha1-induced platelet aggregation, glucosylgalactosyl hydroxylysine, inhibited the alpha1 binding. These results suggest that alpha1(I) chains bind to specific receptor site(s) on platelet membranes to trigger aggregation and the release reaction.


Kinetics of serum amyloid protein A in casein-induced murine amyloidosis. Serum amyloid protein A (SAA), the precursor of secondary amyloid protein, is elevated in chronic diseases which are associated with an increased incidence of amyloid. However, SAA is also elevated in acute bacterial and viral infections and somes forms of cancer. The murine model of casein-induced amyloidosis was studied to determine the relationship between SAA production and amyloid deposition. SAA levels measured by radioimmunoassay were found to be as high as 200 times the normal level in CBA/J mice receiving daily parenteral casein. After a single injection of casein the SAA level was elevated by 3h and peaked by 12-18 h. Similar levels were found in casein-treated A/J mice, a strain less susceptible to the induction of amyloid. Parenterally administered bovine serum albumin, which has low potential for amyloid induction, gave SAA levels in CBA/J and A/J mice comparable to casein treatment. These data show that, while SAA levels are elevated during chronic antigenic stimulation, there are other factors involved in amyloid formation. These factors may include alterations in the degradation of SAA by the reticuloendothelial system caused by substances such as casein. Nude (athymic) mice were shown to attain high levels of SAA after receiving casein parenterally. Therefore, thymus-derived lymphocytes are not necessary for the synthesis of SAA.


Neutrophil preservation: the effect of short-term storage on in vivo kinetics. A rabbit model was developed to study the in vivo viability of neutrophils stored in vitro for up to 72 h. Acid-citrate-dextrose anticoagulated whole blood was obtained from rabbits previously injected with tritiated thymidine ([3H]thymidine), stored under varying conditions, and then injected into recipient rabbits. Neutrophil viability and function were assessed by measuring the ability of the tagged neutrophils to circulate and to migrate into subcutaneous polyvinyl sponges. Unstored neutrophils disappeared exponentially from the circulation with a t1/2 of 3.2 h and gave a zero time recovery of 30.5%. Storage of cells at either room temperature or 4 degrees C for 24 h or longer resulted in temporary sequestration of cells from active circulation. With cells stored for up to 72 h at 4 degrees C, recovery returned to normal values after 1-2 h. Room temperature stored cells, in contrast, showed evidence of irreversible damage at 48-h storage with low recovery for the entire time span studied. With unstored blood, 8.1+/-0.9% of the injected neutrophil label was present in the subcutaneous sponges. The accumulated label progressively decreased as cell storage time increased reaching at 72 h 5.1+/-0.6 and 2.6+/-0.3% for 4 degrees C and room temperature-stored cells, respectively. The results of this study indicate that 4 degrees C storage of rabbit neutrophils is superior to storage at room temperature. The data suggest that it may be feasible to store neutrophils at least a few days without loss of in vivo functions.


Inhibition of antigen- and mitogen-induced human lymphocyte proliferation by gold compounds. Gold sodium thiomalate (GST) inhibited in vitro antigen- and mitogen-triggered human lymphocyte DNA synthesis. Inhibition of responsiveness was observed with concentrations of GST equivalent to gold levels found in serum or tissues of patients receiving chrysotherapy, Inhibition was dependent upon the gold ion itself since GST and gold chloride were both inhibitory whereas thiomalic acid was not. Inhibition could not be explained by nonspecific killing of cells or by an alteration in the kinetics of the responses. GST inhibited mitogen-induced proliferation most effectively when present from the initiation of culture and could not inhibit the responsiveness of cells which previously had been activated by concanvalin A. These findings indicated that GST blocked a critical early step in lymphocyte activation. The degree of GST-induced inhibition of proliferation was increased in cultures of cells partially depleted of monocytes. Moreover, inhibition was reversed by supplementation of these cultures with purified monocytes. These observations suggested that GST blocked thymus-derived (T)-lymphocyte activation by interfering with a requisite function of the monocyte population in initiating such responses. Prolonged incubation of peripheral blood mononuclear cells with GST resulted in diminished mitogen responsiveness upon subsequent culture in the absence of gold. The addition of fresh monocytes restored responsiveness to these populations. Furthermore, preincubation of purified monocytes with GST rendered them deficient in their ability to support mitogen-induced T-lymphocyte proliferation on subsequent culture. These observations indicate that the major effect of GST results from interference with the functional capability of the monocyte population.


Measurement of pulmonary capillary blood flow in infants by plethysmography. An accurate method for measuring effective pulmonary capillary blood flow (Qc eff) in infants has been developed with an adaptation of the plethysmographic technique. Measurements were made on 19 preterm. 14 small-for-dates, and 7 fullterm normal infants with a constant volume whole body plethysmograph in which the infant rebreathed nitrous oxide. There was a highly significant correlation between Qc eff and body weight, and this relationship was unaffected by premature delivery or intrauterine growth retardation. Mean Qc eff in preterm, small-for dates, and fullterm infants was 203, 208 and 197 ml min-1 kg-1, respectively, with no significant differences between the groups. A significant negative correlation existed between Qc eff and haematocrit in the preterm infants. There was no relationship between weight standardized Qc eff and postnatal age in any of the groups. With this technique, it was possible to readily recognise the presence of rapid recirculation (indicative of shunting) in several of the infants, suggesting that rebreathing methods for the assessment of Qc eff should not be applied indiscriminately during the neonatal period. By taking care to overcome the potential sources of technical error, it was possible to obtain highly reproducible results of Qc eff in infants over a wider age range than has been previously reported.


Effects of hypercapnia and inspiratory flow-resistive loading on respiratory activity in chronic airways obstruction. The respiratory responses to hypercapnia alone and to hypercapnia and flow-resistive loading during inspiration were studied in normal individuals and in eucapnic and hypercapnic patients with chronic airways obstruction. Responses were assessed in terms of minute ventilation and occlusion pressure (mouth pressure during airway occlusion 100 ms after the onset of inspiration). Ventilatory responses to CO2 (deltaV/deltaPCO2) were distinctly subnormal in both groups of patients with airways obstruction. The two groups of patients, however, showed different occlusion pressure responses to CO2 (deltaP100/deltaPCO2): deltaP100/deltaPCO2 was normal in the eucapnic patients but subnormal in the hypercapnic patients. Flow-resistive loading during inspiration reduced deltaV/deltaPCO2 both in normal subjects and in patients with airways obstruction. The occlusion pressure response to CO2 increased in normal subjects during flow-resistive loading but remained unchanged in both groups of patients with chronic airways obstruction. These results indicate that while chemosensitivity as determined by deltaP100/deltaPCO2 is impaired only in hypercapnic patients with chronic airways obstruction, an acute increase in flow resistance elicits a subnormal increase in respiratory efferent activity in both eucapnic and hypercapnic patients.


Metabolic clearance and secretion rates of subunits of human thyrotropin. Metabolic clearance rates (MCR) of the alpha and beta subunits of human thyrotropin (hTSH-alpha and hTSH-beta) were determined by a constant infusion to equilibrium method. In 15 normal individuals (six men, six premenopausal women, and three post-menopausal women), the mean MCR of hTSH-alpha (68 ml/min per m2) was significantly faster than that of hTSH-beta (48 ml/min per m2) was significantly faster than that of hTSH-beta (48 ml/min per m2); both were two to three times more rapid than the previously determined MCR of hTSH. In patients with primary hypothyroidism, MCR were significantly slower with a mean value of 55 ml/min per m2 for hTSH-alpha and 37 ml/min per m2 for hTSH-beta. However, MCR of subunits were not significantly faster than normal in hyperthyroid patients. Serum concentrations of alpha subunits and hTSH-beta were measured by radioimmunoassay, and secretion rates of alpha and hTSH-beta from the pituitary were calculated using hTSH-alpha and hTSH-beta MCR, respectively. In the normal individuals, alpha secretion rates averaged 91 mug/day per m2, greater than those previously determined for hTSH and human follicle-stimulating hormone. Alpha secretion rates were significantly elevated in the normal postmenopausal women (211 mug/day per m2) and in the premenopausal hypothyroid women (202 mug/day per m2); they were also elevated in the postmenopausal hypothyroid women (277 mug/day per m2). Alpha secretion rates were significantly decreased in the premenopausal hyperthyroid women (66 mug/day per m2). Usually, the secretion rates of hTSH-beta could not be calculated in normal individuals, and the rates in hyperthyroid patients could never be calculated because serum hTSH-beta was not detected. Six normals had detectable hTSH-beta secretion rates (17 mug/day per m2); hTSH-beta secretion rates were significantly increased in patients with primary hypothyroidism (28 mug/day per m2). Although we had previously demonstrated a 50-fold increase in hTSH secretion rates in primary hypothyroidism, there was only a 2-fold increase in alpha and hTSH-beta secretion rates. Thus, increased subunit synthesis appears to be utilized predominantly for production of complete hTSH.


Induction of arthritis by purified cell-derived chemotactic factor: role of chemotaxis and vascular permeability. The injection of monosidium urate-induced chemotactic factor into the joint cavities of rabbits induces an acute inflammatory response that resembles the one produced by monosodium urate crystals. The leukocyte accumulation induced by the factor was not accompanied by a measurable increase in vascular permeability as measured by appearance of 125I-albumin in the joint cavity. When histamine was injected into the joints, a marked increase in vascular permeability but no leukocytosis above control levels was observed. The above results suggest that the cell-derived factor is primarily responsible for the accumulation of cells seen in the acute inflammation induced by monosodium urate crystals.


Pseudomembranous colitis.

Pseudomembranous colitis. Three basic histopathological patterns which may be seen in rectal biopsies from patients with pseudomembranous colitis are described, based on a study of 29 cases. The spectrum of change is illustrated and the problems of differential diagnosis are discussed--from a non-diagnostic proctitis at one extreme to acute ischaemia at the other. In the differential diagnosis of the acute colitic, the importance of urgent rectal biopsy and a carefully taken drug history is stressed. The association of pseudomembranous colitis with pre-existing disease and antibiotic therapy is confirmed. It is suggested that these cause local mucosal damage and may trigger the first part of a local Shwartzman reaction. Capillary microthrombosis may then paly a part in producing the mucosal necrosis seen later in the disease.


Rapid electron microscopy in oncology.

Rapid electron microscopy in oncology. The case is argued for wider use of electron microscopy as an aid to histological diagnosis in problem cases such as tumours of uncertain histogenesis. In practical terms, electron microscopy can produce results as "immediate" as many special stains in regular use. The cost of providing an effective service can be favourably compared with that of various other diagnostic aids commonly called upon in normal clinical practice. It is suggested that exploitation of this growth area of morphological pathology will enhance the attractions of the discipline of histopathology to talented potential recruits.


Crystals in brain and meninges in primary hyperoxaluria and oxalosis. A case of primary hyperoxaluria and oxalosis with chronic renal failure, crystalline myocarditis, and disseminated calcium oxalate crystal deposition in various tissues including the brain and meninges is described. Deposition of crystals in brain and meninges is exceptionally rare in primary oxalosis.


Avian erythrocyte agglutination tests with the sera of bird fanciers. The agglutination of avian red cells, particularly pigeon and budgerigar cells, by sera from patients who had been exposed to birds and had respiratory symptoms, as well as from healthy bird fanciers, has been used to detect the presence of avian specific antibody. Agglutination tests performed by standard techniques using bird erythrocytes can be read within 45 minutes. One hundred and sixty-five sera were tested, and the 44 which were precipitin positive gave a positive agglutination test with one exception. Of 61 sera which gave positive agglutination tests, 43 gave positive precipitin tests with unconcentrated serum and seven others after fourfold concentration of the serum. Avian antibodies were demonstrated in the remaining 11 sera by radioimmunoelectrophoretic tests. Absorption of the sera with pigeon IgG and IgM and the use of animal antisera directed against pigeon IgG showed that the agglutination reactions were mediated by antibodies directed against pigeon IgG and IgM, and against light chains derived from pigeon IgG.


Susceptibility of the "penicillinase-resistant" penicillins and cephalosporins to penicillinase of Staphylococcus aureus. The activities of some semisynthetic penicillins and cephalosporins have been tested against clinical strains of Staphylococcus aureus. The apparent activity in vitro varies with the method of testing used. Determination of MICs using light inocula fails to detect the destructive effect of penicillinase on the antibiotic. This was, however, demonstrated reproducibly by the use of a technique in which a heavy inoculum was pre-incubated for two hours before application of antibiotic to wells. This method of testing probably represents most of the clinical situations in which the drugs are used since both in vitro and in vivo a growing culture is exposed to an antibiotic gradient. Flucloxacillin was inactivated by penicillinase considerably more than either methicillin, cloxacillin, or nafcillin. Cephaloridine was the most vulnerable of the cephalosporins. Cephazolin, cephalothin, and cephalexin were intermediate. Cephradine was the least hydrolysed by staphylococcal penicillinase. It is recommended that the activities of all penicillins and cephalosporins against staphylococci should be tested by diffusion at 37 degrees C with pre-incubation of the culture for two hours at this temperature.


Antibiotic-resistant Staphylococcus aureus in dermatology and burn wards. Staphylococcus aureus isolated between 1967 and 1975 from the nose and skin lesions of patients in dermatology wards and from the burns of patients in a burns unit in Birmingham showed a high incidence of multiple antibiotic-resistant strains in both environments. Over 20% of the strains isolated from patients on admission to the dermatology wards were multiresistant. Resistance to benzylpenicillin, tetracycline, erythromycin, and fusidic acid was common in the dermatology wards; a smaller proportion of strains were resistant to lincomycin, and few (since 1972 none) were resistant to methicillin; resistance to novobiocin and chloramphenicol was uncommon. In the burns unit, fusidic acid resistance was uncommon, but resistance to benzylpenicillin, tetracycline, erythromycin, novobiocin, neomycin, methicilin, and lincomycin was common. Several of the antibiotics to which resistance was common in the burns unit were rarely if ever used there; strains resistant to these antibiotics probably remained common in the ward through the frequent use of other antibiotics, especially erythromycin, to which these strains were also resistant.


Development and use of a micro haemagglutination inhibition (HAI) technique, based on Hepatest, for the detection and quantitation of hepatitis B surface antibody (Anti-HBs) in blood donors. A simple micro haemagglutination inhibition technique, based on Hepatest (Wellcome Reagents Limited), is described. Its application in the screening of blood donors is shown, and its sensitivity is discussed in two forms of usage and also when compared to the previous immunoelectroosmophoresis technique used in this centre.


Haemocytometry by laser-beam optics: evaluation of the Hemac 630L. Hemac is an automated blood counting system which is based on production of impulses from light scattered and diffracted by cells flowing past a laser beam. The pulses are processed electronically for cell counts and packed cell volume; haemoblobin is measured as cyanmethaemoglobin; absolute values are computed. On evaluation the precision was of the order of 2% for Hb and RBC, 2-8% for PVC, and 3% for WBC. When compared with other methods in the routine laboratory, PCV and absolute values gave divergent results, but PCV was found to correlate well with microhaematocrit corrected for trapped plasma. This suggests that Hemac may more closely reflect true values of PCV, MCV, and MCHC than other routine methods. Whether this "accuracy" is necessarily an advantage must be considered ietation of the blood count data, especially MCV, are discussed.


The platelet count in pregnancy.

The platelet count in pregnancy. The platelet count was measured at approximately monthly intervals during the course of 44 normal pregnancies. There was no evidence of any fall in the platelet count during pregnancy. Any significant change in the platelet count in pregnant women is unlikely to be the result of a normal pregnancy.


Reduced oxidase activity in the caeruloplasmin of two families with Wilson's disease. Caeruloplasmin has been determined immunologically and by coper oxidase activity in 25 normal subjects, 20 patients with Wilson's disease, and 80 patients with chronic liver disease. Repeated estimation in four patients with Wilson's disease and two heterozygous mothers from two families revealed a consistent reduction in the copper oxidase activity of caeruloplasmin (12-32 units copper oxidase activity/mg caeruloplasmin) relative to the values obtained in normal subjects, patients with chronic liver disease, and other Wilson's disease patients (mean 65-79 units/mg). It is suggested that the functional abnormality in caeruloplasmin observed in these two families is an inherited variant, which does not appear to be due to the presence of a serum inhibitor of copper oxidase.


A sensitive urine-test method for monitoring the ingestion of isoniazid. A method is described for monitoring the ingestion of isoniazid based on detecting its metabolites, isonicotinic acid, and isonicotinylglycine in the urine. The sensitivity of the method is high so that reliably positive results were obtained up to about 24 hours after the ingestion of 100 mg isoniazid. The method should facilitate monitoring the taking of isoniazid by tuberculosis patients and the use of isoniazid as a marker for assessing the regularity with which other drugs prescribed for self-administration are actually ingested.


Cat cones have rod input: a comparison of the response properties of cones and horizontal cell bodies in the retina of the cat. The responses of horizontal cell bodies and cones in the retina of the cat have been studied by means of intracellular recording and Procion dye injection in an isolated, arterially perfused eyecup preparation. Comparison of the hyperpolarizing responses of these units to red and blue stimuli of different intensities indicated that all morphological varieties of horizontal cells and, additionally, cones themselves, had mixed rod and cone input. The rod input into horizontal cell bodies is thus explained on the basis of cone physiology. The half-saturating intensity of 441 nm stimuli for the rod input into cones and horizontal cells was about 400 quanta/mum2/sec and about 160,000 quanta/mum2/sec for the cone input. Little of this difference can be related to the different quantum catching abilities of rods and cones. The spatial properties of horizontal cell bodies and cones have been characterized using stimuli consisting of long slits in conjunction with a continuous cable model. Space constants for horizontal cells ranged from 210 mum to 410 mum, whereas those for cones ranged from 50 mum, or possibly less, to 180 mum. It is argued that horizontal cell bodies of the cat retina form electrical networks, and that the sizes of the receptive fields generated in these networks may be limited by the diameters of the primary and secondary dendrites of horizontal cells. The rod and cone fields of horizontal cell bodies were found to be nearly coextensive in space, arguing against the notion that substantial rod input came from distant, rod-dominated terminal arborizations.


The ultrastructure of cutaneous type I mechanoreceptors (Haarscheiben) in cats following denervation. Denervation of specialized cutaneous mechanoreceptors (Haarscheiben or domes) in cats was followed after 20 and 25 days by the following alterations in receptor structure: (1) reduced numbers of Merkel cells, (2) Merkel cells degenerating in situ, (3) fewer dense-core granules in the cytoplasm of Merkel cells, (4) an increased number of agranular dendritic cells and Langerhans cells in the dome, (5) the apparent phagocytosis of Merkel cells by Schwann and Langerhans cells, (6) fewer epithelial cell layers over the dome, and (7) a decrease in the number of transitional cells. Skin excised between the domes in the denervated nerve field appeared normal when compared to innervated skin, and it was considered unlikely that the alterations in dome structure were due to generalized nutritional changes in the skin caused by transection of sympathetic axons or to some other side effect of denervation. Since domes are formed in new locations on the skin after nerves have regenerated (Burgess et al., '74), changes in dome structure following nerve transection are probably due to loss of the "trophic" influence of the nerves supplying the dome.


Unmyelinated axons in thoracic ventral roots of the cat. This study shows that approximately 30% of the axons in the T11 and T12 ventral roots of the cat are unmyelinated. The unmyelinated axons fall into two categories. Slightly less than half are efferents from the spinal cord and slightly more than half arise from dorsal root ganglion cells. The efferent fibers are regarded as unmyelinated preganglionic sympathetics, the fibers of dorsal root ganglion origin are regarded as sensory. This organization of the T11-T12 ventral roots, which are part of the sympathetic outflow, is similar to that of cat ventral roots S3 and Cal, which are part of the parasympathetic outflow, but different from cat ventral roots L7 and S1, which are between the visceral outflows.


The effect of superior colliculus lesions upon the visual fields of cats with cortical ablations. The visual fields of 18 cats were measured before and after various lesions. Preoperatively, all cats had identical fields. With both eyes open, they saw from 90 degrees left to 90 degrees right; with one eye, from 90 degrees ipsilateral to 45 degrees contralateral. Thus the field for nasal retina extends from 90 degrees ipsilateral through to the midline; for temporal retina, from the midline through to 45 degrees contralateral. In summary, postoperative testing led to two major conclusions. (1) Large occipito-temporal cortical lesions produce a stable field blindness, but the blindness is alleviated by a transection of the commissure of the superior colliculus (or a unilateral collicular ablation). This transection yields the same result whether it occurs in an operation before, during, or after the cortical lesion. These data confirm and extend the Sprague effect. (2) Cats made dependent upon retinotectal pathways due to cortical ablations responded much better to stimulation of nasal retina than to stimulation of temporal retina. This presumably is related to the preponderance of nasal retina as a source of the retinotectal pathway. Since even smaller cortical lesions limited to areas 17, 18, and 19 produce this nasal/temporal retinal difference, it is concluded that integrity of the geniculocortical pathways is necessary for good temporal retinal vision as determined by these methods.


The effect of cortical and tectal lesions on the visual fields of binocularly deprived cats. The visual fields of seven cats raised with binocular lid suture were measured before and after various neural lesions. Each of the cats preoperatively responded with each eye to stimuli from 90 degrees ipsilateral through to the midline. A transection of the optic chiasm rendered one cat blind on the visual field tests. Large bilateral occipito-temporal cortical ablations (4 cats) did not measurably affect orienting responses or the extent of visual field. Unilateral occipito-temporal cortical ablations (2 cats) also had no affect on the visual fields, but subsequent ablations of the contralateral superior colliculus produced permanent blindness in the hemifield contralateral to the ablated tectum. These two cats also were apparently blind with the eye contralateral to the ablated tectum; but with the other eye, the cats retained their preoperative orienting responses. These data are consistent with the hypothesis that, with early binocular deprivation, cats develop dependence upon retinotectal and not thalamocortical pathways for visually guided orienting behavior.


Response of the three main types of glial cells of cortex and corpus callosum in rats handled during suckling or exposed to enriched, control and impoverished environments following weaning. The cell populations of the occipital cortex were examined in young rats subjected to different sensory experiences. In one series recently weaned animals were reared in enriched, impoverished or control environments. The enriched environment was obtained by keeping the animals among "toys" and other rats; the impoverished environment, by rearing the animals one per cage in a darkened, quiet room; and the control environment, by housing the animals three per cage under usual animal room conditions. Six recently weaned rats were kept in each environment for 30 days and ten, for 80 days. In a second series suckling rats were handled daily. Handling consisted of touching, holding and rubbing rat pups for 15 minutes per day during the first ten days after birth; twelve rats were studied, six handled and six unhandled controls. In the two series, the animals were sacrificed under anesthesia by perfusion with mixed aldehydes. Semithin epon sections of occipital cortex were stained with toluidine blue; neurons and the three main types of glia were enumerated. In addition, the thickness of the cortex was measured and the glial cells of corpus callosum counted in the animals exposed to the three environments for 80 days. Under the influence of the enriched environment, the occipital cortex enlarged, the number of oligodendrocytes increased over the controls by 27-33% in the 30- and 80-day groups and the number of astrocytes, by 13% in the 80-day group. Within the cortex, only certain layers showed the increase in glial numbers. In the corpus callosum, however, the numbers of glial cells did not differ from those in controls. In the animals exposed to the impoverished environment, neither the size of the cortex nor the number of oligodendrocytes and astrocytes differed from controls. The animals subjected to handling also showed evidence of cortical enlargement, but the only significant change in glial cells was a 12% increase in astrocytes. It is concluded that handling and enrichment produce changes in anatomical indices of neural function including depth of cortex and numbers of glial cells. The glial response was specific to the type.of manipulation since astrocytes were predominantly affected by handling and oligodendrocytes, by enrichment. The effect of handling on astrocytes may be attributed to the stimulation being applied at a time of astrocyte proliferation, whereas the effect of enriched environment on oligodendrocytes occurred at a time of active production of these cells. The differences in cell numbers were explained by changes in the rate of cell population growth; since the impoverished did not differ from the control animals, the changes probably consisted of growth acceleration in the enriched animals rather than diminution in the impoverished ones.


Quantitative studies of cell size in the cat's dorsal lateral geniculate nucleus following visual deprivation. The effects of visual deprivation upon dorsal lateral geniculate (DLG) cell size were compared for seven kittens reared with monocular lid-suture (MD), seven with binocular lid-suture (BD), and six with one eye lid-sutured and the other eye enucleated soon after birth (MD-E). Six additional kittens were reared normally for comparison. For each kitten the cross-sectional areas of 300 cells were measured in one or both nuclei. Measurements were taken from the binocular segment of laminae A and A1 and the monocular segment of lamina A. In agreement with previous studies, cells in the binocular segment of the deprived laminae of MD cats were smaller (33-34%) than those in the non-deprived laminae. Comparisons with normal animals indicated that this difference was due to an increase (10-15%) in size of cells in the non-deprived laminae as well as a decrease (23-25%) in size of cells in the deprived laminae. Cells in the monocular segment also were affected by deprivation in MD cats, and this effect increased with the age (and duration of the deprivation) of the animal. However, it was always smaller than the decrease in cell size in the binocular portion of the DLG. In BD kittens, DLG cells were smaller (7-12%) than normal in all portions of the nucleus, including both the binocular and monocular segments. Direct comparisons between the deprived laminae of MD and BD kittens indicated that the decrease in cell size was greater for MD kittens in the binocular segment, but tended to be greater for BD kittens in the monocular segment. In MD-E kittens, DLG cells in the deprived laminae were smaller (11-17%) than normal in all portions of the nucleus, including both the binocular and monocular segments. Thus, the effects of deprivation were similar to those in BD kittens, even though inputs from the deprived eye had been placed at a competitive advantage in MD-E kittens. These results indicate that two factors may affect cell size in the DLG of visually deprived cats: deprivation per se and abnormal binocular competition. Finally, separate analyses for the ten largest and the ten smallest cells in each lamina of each cat were carried out in an attempt to determine if the changes in cell size were limited to the largest cells. In every case, differences observed for the total sample of cells were paralleled by differences from normal of both the largest cells present and the smallest cells present in the deprived laminae. Since at least two alternative interpretations can account for this finding, the question of whether the large cells are selectively affected by visual deprivation remains unanswered in the cat.


Hair cell distribution and orientation in goldfish otolith organs. Structurally diverse sensory regions occur in the otolith organs of the goldfish inner ear. Scanning electron microscopy reveals regional distinctions based on three criteria. (1) Hair cells have different sizes of apical bundles, based on thickness. In all three maculae, two central regions have hair cells with bundles significantly thicker than those in surrounding regions. (2) Hair cell population density varies, with regional aggregations present. The central regions with thick bundles have two to three times the density of surrounding regions with thin bundles, and contain 40-80% of the total hair cell number in each macula. (3) Hair cell orientation maps show that each macula has two oppositely oriented cell populations that can be separated completely, not by a zone of interspersion, but apparently by a single unbroken line. The lagena is like the utricle in having hair cells with the kinocilium on the side of the cell toward the opposition line, but in the saccule the kinocilia face away from the line, and the small macula neglecta consists of two completely separate, oppositely oriented patches. The opposition line does not divide each macula simply down its midline; instead, the line divides the regions with thich bundles into nearly equal opposing areas, except for a remarkably abrupt large loop in the line in the anterior part of the saccule. The regional structural diversity in these organs may relate to localized functional diversity of responses to tilt, vibration and sound.


The vestibular complex of the American opossum, Didelphis virginiana. I. Conformation, cytoarchitecture and primary vestibular input. Degeneration experiments reveal that the vestibular nerve of the adult opossum distributes to an extensive and diverse area of the brainstem and, as in placental mammals, the traditionally named nuclei do not receive a uniform distribution of primary afferent fibers. Nevertheless, such nuclei as well as other nearby cell groups have been considered as vestibular since they share other mutual connections. Except for subgroups "l", "g" and the nucleus supravestibularis all of the vestibular subdivisions generally recognized in more specialized placentals (e.g., the cat) have been identified in the marsupial opossum. Each of the vestibular nuclei and "extra-nuclear" cell stations are described as to their boundaries, cytoarchitecture and dendritic domain. Whenever possible we have employed a terminology consistent with that used for the cat. In several instances we have used results from experimental degeneration material to identify nuclear boundaries and divisions which are not apparent in routine Nissl, Golgi or silver preparations.


Second order auditory pathways in the chimpanzee. Substantial portions of the dorsal, and almost the entire posteroventral and anteroventral (Av) cochlear nuclei were aspirated unilaterally in a chimpanzee. Axonal degeneration was studied by the Fink-Heimer method. The greatest amount of degeneration was followed medially from the region of Av into the lateral part of the trapezoid body. Degeneration also coursed around the superior surface of the restiform body and was traced into the dorsal and intermediate acoustic striae. Within the superior olivary complex, degeneration was distributed to: the ipsilateral lateral superior olive; laterally and medially oriented dendrites of the ipsilateral and contralateral medial superior olivary nuclei respectively (some perisomatic degeneration also was present bilaterally); the contralateral medial trapezoid nucleus; retro-olivary and preolivary cell groups bilaterally. Abundant degeneration passed into the contralateral lateral lemniscus and was distributed largely to its ventral nucleus. The contralateral central nucleus of the inferior colliculus was a major site of termination of ascending second order auditory fibers. The caudal tip of the ipsilateral ventral nucleus of the lateral lemniscus received abundant degeneration, but this diminished rostrally. The ipsilateral inferior colliculus contained a moderate amount of degeneration. A fair number of degenerated second order auditory fibers ascended in the contralateral brachium of the inferior colliculus and were distributed both to the principle and magnocellular divisions of the medial geniculate body. This pathway appears to represent a phylogenetic advance in the brain of the great ape.


The locust wing hinge stretch receptors. I. Primary sensory neurones with enormous central arborizations. In locusts a single-celled stretch receptor (SR) neurone at the base of each wing monitors wing elevation and contributes to the control of the flight motor output. The central projections of these neurones are very complex but consistent in detail in the three species studied (Chortoicetes, Locusta and Schistocerca). The hindwing SR projects to the second and third thoracic ganglia, the forewing SR to the first, second and third thoracic ganglia. Both send fine axons into the abdominal connective. Within the ganglia each SR forms an extensive arborization, entirely ipsilateral and mainly in the dorsal neuropile, divided into medial, mediolateral, and lateral branches. The projections of the two ipsilateral SR neurones overlap almost completely in the second and third ganglia. There are recurrent loops between branches of a single neurone both within and between ganglia. Light microscope analysis shows apparent contacts between the SR aneurones and flight motor neurones and other wing sensory afferents, as well as long interneurones, other motor neurones and two types of multiaxonal neurones of unknown function. There are three groups of contacts between each SR and a flight motor neurone: laterally on the main branches, medially with the terminal twigs; and in the anterior dorso-medial glomerulus, where the inter ganglionic recurrent branch also terminates. All contacts are ipsilateral except for those with the contralateral branches of the dorsal longitudinal muscle motor neurones. We suggest that the SR neurones are multifunctional. Differential information transfer could result both from the spatial distribution of synaptic connections with the motor neurones and from filtering caused by low safety factors at branch junctions. Information in the lateral branching could be used for general excitation and control of firing frequency of the motor neurones; that in the medial branch for wing control and co-ordination.


The locust wing hinge stretch receptors. II. Variation, alternative pathways and "mistakes" in the central arborizations. The central arborizations of the stretch receptor (SR) neurones are very consistent from one individual to another. Superimposition of normalized neurones from eight individuals of Locusta show very little variation even in the detailed branching pattern. There is, however, a commonly found alternative course for the main medial branch in the metathoracic ganglion. Rare, radical departures from the normal branching pattern are termed "mistakes." Only three have been found, all in the forewing SR projection, one with an extra branch and two with missing branches. Terminals of twigs in the alternative region of the medial branch occupy consistent positions in the neuropile, although these are reached by different routes. Mistakes have terminals in areas normally containing SR endings. Both these findings suggest that there may be labelled sites in the neuropile which the growing tips of the SR neurones seek out.


Visual cortical areas mediating form discrimination in the cat. Cats were trained pre- and/or postoperatively on flux and pattern discriminations, and were examined in a series of visuomotor tests which measured attention and orientation to, and following and localization of stationary and moving stimuli, in a free situation and in a perimetry test. Cortical lesions were placed in areas 17 and 18, or in the middle and posterior suprasylvian gyri and sulci--areas 19, 20, 21, 7 and lateral suprasylvian cortex (LSA), as delineated by cyto- and myeloarchitecture, and by electrophysiological mapping. After removal of all of area 17 and up to 90-95% of 18, postoperative learning of flux and pattern discriminations is at a high level, although in some cases slowed. Visuomotor behavior is normal. Such lesions result in severe atrophy only of laminae A, A1 and C in the lateral geniculate nuclear complex (LGNd). The neuronal systems for perceiving and discriminating simple, large planimetric patterns and forms, and for mediating visually guided behavior characteristic of this species lie outside of areas 17-18. The cortices primarily responsible for form discrimination in the cat include those in the suprasylvian gyri and sulci. After lesions which removed areas 19, 20, 21 and LSA, sparing most of 17-18, form discriminations based on orientation or shape were prolonged or absent. Although these animals showed slow tracking and poor depth judgment, the visual fields were full and they had good sensory and perceptive capacity as seen in normal flux and near normal pattern (gratings) discrimination. Such lesions result in severe atrophy in lateral and inferior pulvinar complex. Although these nuclei receive visual input primarily from the superficial laminae of the superior colliculus and certain nuclei of the pretectum, both areas 19 and LSA receive a dual input from pulvinar and parts of LGNd. Whether these marked deficits in form discrimination after suprasylvian lesions are due to involvement of certain crucial areas of this extensive cortex, or whether all are involved in some integrated fashion, is not yet completely clear. Removal of 19, 21 and parts of LSA are followed by similar (but somewhat less marked) deficits of both retention and learning. Lesion in area 20 alone (cortical target of the lateral pulvinar) leaves retention of preoperatively learned discriminations intact but results in prolonged initial learning. Previous work by the present authors has shown similar deficits in form discrimination in the cat after lesions in the pretectum-superior colliculus. These data, together with the present findings appear to support the hypothesis that the midbrain-pulvinar-cortical pathways provide the first stage in simple, coarse form perception and discrimination in this species.


Specific neuroanatomical changes in chemosensory mutants of the nematode Caenorhabditis elegans. Eight of nineteen chemotactic mutants of the nematode Caenorhabditis elegans have morphological defects in the sensory endings of neurons at the tip of the head. The mutants were obtained as worms swimming away from attractant or found amongst male potency mutants or mutants exhibiting erratic behavior. The nineteen mutants fall into at least twelve complementation groups. Mutants E1034 and E1035, alleles of che-1, show morphological alterations in the sensory endings of amphidial neurons and inner labial type 2 neurons, both prospective chemosensory neurons. Both mutants contain non-complementing ts sterile mutations linked to the chemosensory mutation. E1066 shows abnormalities in all the sheath cells associated with the sensory neurons and in the bundling pattern of the amphidial neurons. E1126 is structurally abnormal only in the sensory endings of inner labial type 2 neurons, supporting a chemosensory role for these neurons. E1033 (che-2) and E1124 (che-3) cause defects in the ciliary structure of all but one type of ciliated sensory neuron in the head. E1062 is grossly defective in head structure and the structure of the male copulatory organ, suggesting these opposite ends of the nematode rich in sensory structures share gene functions in embryogenesis. Our study illustrates the possibilities for genetic dissection of the development of a small set of nerves in a simple organism.


Preterminal and terminal axon arborizations in the substantia gelatinosa of cat's spinal cord. Extensive terminal branchings of fine fibers in the substantia gelatinosa of Golgi-Kopsch preparations of the adult cat spinal cord were subjected to a semi-quantitative analysis. transverse sections suggest that these fibers are probably unmyelinated primary afferent elements of dorsal root origin. In transverse sections these elements pass medially and ventrally and shortly disappear due to a change in orientation. Similar thin fibers in sagittal sections can be followed for several hundred microns as they give rise to side branches that also run mainly in a longitudinal direction. The side branches divide in turn to produce preterminal axon arborizations. The arborizations were distributed in 150 mum wide zones in the dorsal horn region corresponding to Rexed's lamina II. The end terminals are large bulbs, usually preceded by two to three equally large en passant enlargements. Seven to eight terminals stem from each side branch. The terminals and enlargements are arranged in narrow (16-26 mum thick) sagittal sheets. The terminals of several side branches often converge upon a common region so that clusters of terminals occur within the sagittal sheet. It is proposed that these observations are consistent with the substantia gelatinosa (lamina II) as the termination of unmyelinated (C) primary afferent fibers and that the latter are the only type of primary fibers ending in this portion of the spinal cord.


Central connections of ventral root afferents as demonstrated by the HRP method. To study the central connections of ventral root afferents, horseradish peroxidase was injected into the lumbosacral spinal cord of the cat and the appropriate dorsal root ganglia were examined from segments with (1) both dorsal and ventral roots intact, (2) both roots sectioned, and (3) only the dorsal root sectioned. The key finding was that a number of labeled cells (up to 133) were observed in the ganglion after dorsal rhizotomy. We interpret these findings to mean that the central processes of the labeled cells projected to the spinal cord through the ventral root. As expected, when both roots were cut, almost no cells were labeled and when both roots were intact, there were large numbers of labeled cells. Of the labeled cells observed in ganglia after dorsal rhizotomy, all were found to be within the ganglion itself. No labeled aberrant dorsal root ganglion cells could be found.


Regeneration of fungiform taste buds: temporal and spatial characteristics. The gross morphology of the tongue of the Mongolian gerbil Meriones unguiculatus), the location of papillae and taste buds, and the normal innervation pattern of the tongue and taste buds were determined. The chorda tympani nerve was interrupted to produce degeneration of fungiform taste buds. Regenerating chorda tympani axons followed the original nerve pathways in the tongue en route to the fungiform papillae in the epithelium where they initiated the regeneration of taste buds. The spatial distribution of reinnervated fungiform papillae and reformed taste buds was examined 7 to 19 days following surgery. Beginning at eight days following chorda tympani interruption there was a progressive increase, first, in the proportion of fungiform papillae that were reinnervated, and later in the number of reformed taste buds. On the basis of these measures it was concluded that a taste bud is reformed one to two days after reinnervation of its papilla. From the time course of reinnervation of the fungiform papillae it was calculated that some fibers regenerated at rates in excess of 2 mm/day. Regeneration was precise and systematic. The regenerating chorda tympani fibers accurately returned to the fungiform papillae; they did not follow the pathways of lingual nerve axons. In the initial stages of recovery both reinnervated papillae and reformed taste buds were preferentially located toward the front of the tongue; the reinnervation of posterior fungiform papillae was delayed.


Taste fiber responses during reinnervation of fungiform papillae. Crushing or transecting the chorda tympani nerve of the gerbil (Meriones unguiculatus) caused ipsilateral degeneration of taste buds in the fungiform papillae. In less than two weeks some taste fibers regenerated into the tongue and formed new taste buds and receptor cells. The recovery process was evaluated electrophysiologically in 53 gerbils by acute recording proximal to the nerve injury site. Initially the chorda tympani was electrically silent. In gerbils tested at later times spontaneous activity appeared. This was followed by responses to pressure on the tongue. Taste responses returned as early as day 11. The receptive field of regenerated taste fibers was limited to a small number of fungiform papillae. Taste responses were always associated with the presence of one or more taste buds in the receptive field. Taste buds identified as responsive to chemicals contained some fusiform cells. We found that the taste responses of single fiber, few-fiber and multi-unit preparations reflected the diversity of responses found in normal taste axons as determined by recording from 26 normal single fibers and 27 normal whole nerves. The early emergence of a variety of fiber types and responses to many chemicals in regeneration is inconsistent with the proposition that the relative chemical responsiveness of a receptor cell is strictly a function of its age; the response of a given young taste receptor is not necessarily limited to a few of the standard taste stimulants.


Neurogenesis in the epithalamus, dorsal thalamus and ventral thalamus of the rat: an autoradiographic and cytological study. Times of final mitotic division for neurons of the epithalamic, dorsal thalamic and subthalamic nuclei of the rat were determined with the aid of thymidine-H3 autoradiography. Intensely labelled neurons were observed in the brains of animals injected with radiochemical from days 13 to 19 of gestation. The pattern of distribution of the labelled neurons indicated that neurogenesis in the regions followed caudorostral, lateromedial and ventrodorsal neurogenetic gradients, all of which were found to operate simultaneously. Since neurogenesis in the epithalamus, subthalamus and caudolateral thalamic regions began on days 13 and 14 of gestation, the ventrodorsal and lateromedial proliferative gradients were clearly discerned only within the ventral and dorsal thalamus exclusive of the epithalamus. These directional neurogenetic gradients were apparent throughout the entire thalamus and within individual thalamic nuclei. No neurogenetic pattern based upon neuronal size was observed, i.e., large neurons were not preferentially formed earlier than smaller ones. Detailed information has also been provided on the cytological character of each thalamic nucleus.


Projections from the amygdaloid complex to the cerebral cortex and thalamus in the rat and cat. Projections are described from the basolateral, lateral and anterior cortical nuclei of the amygdaloid complex, and from the prepiriform cortex, to several discrete areas of the cerebral cortex in the rat and cat and to the mediodorsal thalamic nucleus in the rat. These projections are very well-defined in their origin, and in their area of laminar pattern of termination. The basolateral amygdaloid nucleus can be divided into anterior and posterior divisions, based on cytoarchitectonic and connectional distinctions. In both the rat and cat the posterior division projects to the prelimbic area (area 32) and the infralimbic area (area 25) on the medical surface of the hemisphere. The anterior division projects more lightly to these areas, but also sends fibers to the dorsal and posterior agranular insular areas and the perirhinal area on the lateral surface. Furthermore, in the cat the perirhinal area is divided into two areas (areas 35 and 36) and the anterior division projects to both of these and also to a ventral part of the granular insular area; this last area is adjacent to, but separate from the auditory insular area and the second cortical taste area. In most of these areas, the fibers from the basolateral nucleus terminate predominantly in two bands: one in the deep part of layer I and layer II, and a heavier band in layer V (in the rat) or layers V and VI (in the cat). The lateral amygdaloid nucleus projects heavily to the perirhinal area, and also to the posterior agranular insular area. These fibers terminate predominantly in the middle layers of the cortex, although the cellular lamination in these two areas is relatively indistinct. The anterior cortical amygdaloid nucleus and the prepiriform cortex both project to the infralimbic area and the ventral agranular insular area, and the anterior cortical nucleus also projects to the posterior agranular area and the perirhinal area. In all of these areas, the fibers from these olfactory-related structures terminate in the middle of layer I. In the rat, the two divisions of the basolateral nucleus also project to the medial segment of the mediodorsal thalamic nucleus, with the anterior division projecting mainly to the posterior part of this segment and the posterior division to the anterior part. The endopiriform nucleus, deep to the prepiriform cortex, projects to the central segment of the mediodorsal nucleus; this may constitute the major olfactory input into the mediodorsal nucleus, since little or no projection could be demonstrated from the prepiriform cortex itself. Projections to the mediodorsal nucleus have not been found in the cat.


Projections from the amygdaloid complex and adjacent olfactory structures to the entorhinal cortex and to the subiculum in the rat and cat. Axonal projections are described from the lateral and basolateral nuclei of the amygdaloid complex, and from the overlying periamygdaloid and prepiriform cortices and the endopiriform nucleus, to the lateral entohinal area, the ventral part of the subiculum, and the parasubiculum in the cat and rat. All of these projections have well-defined laminar patterns of termination, which are complementary to those of other projections to the same structure. Based on these results, and on cytoarchitectonic distinctions, the lateral entohinal area has been divided into dorsal, ventral, and ventromedial subdivisions. The olfactory bulb and prepiriform cortex project to layers IA and IB, respectively, of all three subdivisions, but the lateral amygdaloid nucleus has a restricted projection to layer III of the ventral subdivision only. The periamygdaloid cortex projects to layer II of the ventromedial and adjoining parts of the ventral subdivisions. The ventral part of the subiculum receives fibers from the posterior division of the basolateral nucleus, which terminate in the cellular layer and the deep half to one-third of the plexiform layer. The periamygdaloid cortex and the endopiriform nucleus also project to the same part of the subiculum, but these fibers terminate in the outer part of the plexiform layer. None of these projections extend into the dorsal part of the subiculum. The posterior division of the basolateral nucleus also projects to the posterodorsal part of the parasubiculum ("parasubiculum a" of Blackstad, '56). These fibers end in the deeper part of the plexiform layer and the superficial part of the cellular layer.


Enhanced response acceleration or suppression produced by response-independent food presentations in rats with septal lesions. In two separate experiments, the response rates of rats with septal lesions were compared with those of control rats when response-independent food was presented while subjects were responding on a differential-reinforcement-of-low-rate schedule of reinforcement (Experiment 1) or according to a conjunctive differential-reinforcement-of-high-rate, fixed-ratio schedule (Experiment 2). Free-food deliveries resulted in acceleration of responding of subjects working on the low-rate schedule and in suppression of responding of those animals working on the high-rate schedule. Both of these effects were localized to a brief time period immediately following the free-food deliveries, and baseline rates of responding were not altered. The acceleration and suppression of responding that occurred on the respective schedules were greatly enhanced in rats with septal lesions. This finding supports the suggestion that these animals are hyperreactive to the reinforcing and/or eliciting properties of discrete stimulus events.


Conditioned insulin secretion and meal feeding in rats. Previous researchers have reported that rats placed upon a feeding regimen such that they receive only 2 hr of food per day (meal-fed rats) develop hyperinsulinemia at the time of the day associated with feeding, even in the absence of food. Controls fed ad lib had no such response. In a series of several experiments, meal-fed rats had elevated insulin levels at only the specific time of the day associated with feeding, and the increment of insulin at that time could be eliminated with atropine. Free-feeding controls, on the other hand, always had higher insulin levels than the meal-fed rats, did not have an elevation of insulin at the time of the day that the meal-fed rats normally ate, and had insulin values that were unaffected by atropine. Further experimentation showed that hyperinsulinemia could become associated with arbitrary stimuli always associated with eating for meal-fed rats. It is concluded that the hyperinsulinemia of meal-fed rats associated with their feeding time is a learned response.


Somatosensory determinants of lordosis in female rats: behavioral definition of the estrogen effect. By coating the ventral surface of male rats with a dye, regions of contact between male and female during male mounting were recorded precisely on the female's hair and skin. The male rat touches the female's flanks, rump, tailbase, perineum, and perivaginal surfaces during the female's initiation and maintenance of lordosis. Film analyses showed that the male's paws and pelvic thrusting stimulate the female's skin with dominant frequencies between 10 and 20 per second. Somatosensory stimuli were applied by the experimenter to the female skin locations contacted by the male. Deflection of hair on the flanks or perineum alone did not cause lordosis. Light stimulation simultaneously on flanks and perineum caused lordosis only in some females given high estrogen dosages supplemented by progesterone. When flank stimuli were followed by pressure on the rump, tailbase, and perineum, lordosis was triggered reliably in hormone-treated females. Here the estrogen-dependence of the reflex was shown, and progesterone synergized with the estrogen effect. Among lordosis components, rump and head elevations in response to pressure stimuli on the rump, tailbase, and perineum appear to be hormone-sensitive. These results help to define the minimal cutaneous sensory requirement for lordosis. In turn, the estrogen effect on lordosis may be defined behaviorally as increased responsiveness to pressure on rump, tailbase, and perineal skin, after flank stimulation. These results illustrate how estrogen, progesterone, and somatosensory stimuli interact in causing lordosis, increases in the strength of one factor compensating for decreases in another.


A factor analytic--genetic approach to the relation between obesity and behavior in mice. Genetically heterogenous mice (N = 377) were reared on either high- or low-fat diets for the first 40 days of life. The mice were cross fostered to permit the separation of genetic and environmental effects in a sibling analysis. A total of 26 measures were taken on these mice, including oxygen consumption, activity, sucrose consumption, body weight changes when bitter or high-fat diets were given as the only food, and various morphological measures. A principal-factor analysis of these measures produced eight factors, most of which appeared to be "instrument" factors rather than general factors. Analyses of variance on the factor scores indicated that genetic influences contributed to five of the factors and sex contributed to three of the factors. However, none of the main effects of diet, gene by environment interactions, or sex by environment interactions were significant. Although obesity and behaviors were correlated, the magnitudes of the correlations were generally small.


Angiotensin-induced dipsogenesis in domestic fowl (Gallus gallus). Both systemic (100 mug, 200 mug, and 400 mug im) and intracranial (75 ng, 150 ng, and 300 ng) injections of Val5-angiotensin II-amide produce copious and dose-related drinking in White Leghorn chickens in normal water balance. Angiotensin-induced drinking has been reported in several mammalian species and in Barbary doves and white-crowned sparrows. The findings reported here extend the species generality of angiotensin-induced thirst and are evaluated in light of current biochemical and pharmacological analyses of the renin-angiotensin system in chickens.


Heart rate and cardiac phase influences on visual perception. Twenty-six subjects were tested with a tachistoscopic recognition task while heart rate and several other autonomic indexes were monitored. In Experiment 1, heart rate was employed as an independent variable, and stimulus presentation was contingent upon the presence of individually determined low, middle, and high heart rates. The results indicated that low heart rate facilitated performance especially for stimuli presented at the fastest exposure. In Experiment 2, stimulus presentation was dependent upon cardiac phase. The findings indicated that stimulus recognition was enhanced during the cardiac P wave, but the effect was apparent only during the fastest exposure. Multiple regression analyses of the individual subject's data during both experiments indicated that highly idiosyncratic patterns of physiological responses predicted perceptual performance. The results were interpreted as being consistent with the formulations of the Laceys and also suggested that cerebral perfusion be considered as a relevant determinant of behavior.