Late endocrine effects of administering monosodium glutamate to neonatal rats

Rats were injected with monosodium 1-glutamate (MSG) daily for the 1st 5 days of life and allowed to mature. This is known to cause selective destruction of neurons in the retina and in the arcuate nucleus of the hypothalamus. The adult animals had a significant increase in body fat without an increase in weight, a marked reduction in pituitary, thyroid, adrenal, gonadal and prostate weights. Pituitary, hypothalamic and serum thyrotropin (TSH) were significantly reduced in the males. Serum growth hormone (GH) was markedly reduced in both sexes and the serum prolactin (Prl) was increased significantly in females. FSH did not appear to be abnormal and the LH may have been increased in the males. Serum T4 was significantly reduced in females. The fertility of the females was normal, but treated males mated with normal females showed a marked reduction in fertility and, although the litter sizes of the offspring were normal, the birth weights of the pups of both sexes were significantly reduced. These persistent alterations in neuroendocrine function indicate that lesions produced by neonatal MSG treatment provide a convenient model for studying hypothalamic function.

The interaction of p-nitrophenyl carbamate with urease

1. p-Nitrophenyl carbamate and thiourea have been shown to be substrates for urease (urea amidohydrolase, EC 3.5.1.5) 2. Urease has been shown to have a lower Km, 0.67 mM, with p-nitrophenyl carbamate than with urea, 2.0 mM. 3. The V of urease for the hydrolysis of urea, p-nitrophenyl carbamate and thiourea has been shown to be the same, indicating a common rate-limiting step. 4. A mechanism has been proposed for urease where the initial rate-limiting step is the release of a molecule of ammonia from the substrates.

Endocrine studies in the untreated F1 and F2 progeny of rats treated neonatally with thyroxine

When neonatal rats are made hyperthyroid with large doses of thyroxine during the first 5 days of life, they develop hypothalamopituitary, thyroidal and gonadal abnormalities that persist through life. When female rats, which have been treated neonatally, are subsequently mated to normal males, their offspring show unexpected gonadal and thyroidal defects, such as reduced weaning weight and delayed vaginal opening and first estrus in females; males show a significant increase in relative thyroid weight and a significant decrease in ventral prostate weight. Cross-fostering was done to separate prenatal from postnatal influences. Even more surprising was the finding that when the untreated female F1 progeny were mated with normal males, the untreated F2 progeny showed more defects and to a greater degree than those present in the maternal parent.

Comparison of intensive versus moderate chemotherapy of lymphocytic lymphomas: a progress report

In an Easter Cooperative Oncology Group trial, Cytoxan-prednisone (CP) Induction was compared to BCNU-prednisone (BP) in 273 patients with lymphocytic lymphoma. Response rates were comparable, with 21% achieving complete response and 40%, partial response. Patients with a nodular pattern responded better. Maintenance phase comparing cyclic intensive therapy (BCVP) with intermittent chlorambucil revealed the superiority of BCVP as demonstrated by improvement of the quality of response and somewhat longer remissions. The value of the Rappaport classification in the evaluation of lymphoma chemotherapy results is discussed. It is suggested tha NHL be separated into "favorable" and "unfavorable" groups, based on the presence or absence of nodularity and treatment schedules devised accordingly.

Suppression of sympathetic nervous function in low-renin essential hypertension

Study of general haemodynamics in 15 patients with low-renin essential hypertension showed haemodynamic and pathophysiological heterogeneity. However, there was suppression of sympathetic nervous system function in all low-renin patients, regardless of haemodynamic pattern. Subnormal sympathetic nervous activity was manifested by a low normal mean plasma-noradrenaline concentration at rest, diminished noradrenaline responsiveness to postural stimulation, and a reduced blood-pressure response to the indirectly acting sympathomimetic amine tyramine. It is proposed that the syndrome of low-renin essential hypertension is of diverse aetiology, but with secondary sympathetic nervous system underactivity as a feature common to the various forms. The low plasma-renin activity is probably an expression of defective sympathetic nervous system stimulation of renin release.

Behavior and single gene substitution in Drosophila melanogaster. I. Mating and courtship differences with w, cn, and bw loci

The effect of single allele substitutions into an isogenic background in Oregon-R inbred lines of Drosophila melanogaster on courtship and mating patterns has been studied. A comparison has been made between the white locus w, wco, we, the wild type w+, cn, bw, and cn bw to test the effect of eye pigmentation in influencing courtship and mating patterns. It was found that w, we, wco, cn, and bw females were more successful in mating than were wild-type and cn bw females, cn bw females being less successful than wild-type females. Also, w and cn bw males were equally successful in mating but less successful than wild-type males during the 20-min test period. The mutant males performed as well as the wild-type after courtship was initiated. The behavioral parameters measured were (1) courtship latency, the time from exposure of male to female until orientation; (2) mating speed, the time from beginning of orientation of male to female until successful copulation, and (3) copulation time.

Observations on the untreated progeny of hypothyroid male rats

The untreated progeny (F1) of hypothyroid male rats that were either radiothyroidectomized (Tx) or had the neo-T4 syndrome (an endocrine disorder produced by large doses of thyroxine (T4) injected during the neonatal period) were studied. The mother rats were all normal. The fathers never had any contact with their progeny. Unexpectedly, the progeny usually showed delayed eye opening, decreased weaning weights, and increased final body weight. The thyroid glands from F1 offspring of both Tx and neo-T4 fathers were enlarged significantly in all but F1 males of Tx fathers. The F1 of Tx fathers had significantly smaller uteri, both absolutely and relatively. The ovaries were significantly larger, whereas the testes were significantly smaller. Pituitary TSH, stalk-median eminence (SME) TSH, and serum TSH were all normal with the exception of an increase in SME TSH in F1 males born of neo-T4 fathers. The response to thyrotropin releasing hormone (TRH) stimulation of the F1 adult progeny of neo-T4 fathers was significantly blunted in the males, whereas the response was normal in offspring of Tx fathers. The mechanisms by which hypothyroid fathers caused changes in their progeny is not known.

Human middle ear corpuscles -- A light and electron microscopic study

The human middle ear corpuscles originally described by von Troeltsch are examined by means of light microscopy in 124 subjects, and electron microscopy in 27 subjects. While the corpuscles are not observed in all 19 individuals under age six, and in all 20 adults who had a history of suppurative otitis media, an average of six corpuscles per temporal bone is found in 98 percent of 83 adult subjects who had no history of middle ear disease. Two-thirds of the corpuscles are located in the mastoid, and the remainder in the middle ear. Often, they become bifurcated or trifurcated. Although light microscopy shows that the corpuscle is formed by lamellar capsules and a central core resembling pacinian corpuscles, electron microscopic study failed to confirm that this structure is a typical pacinian corpuscle. Subsequently, possible physiological significance of this corpuscle is discussed.

The late effects of neonatal hyperthyroidism upon the feedback regulation of TSH secretion in rats

Rats made thyrotoxic with large doses of thyroxine (T4) during the neonatal period (neo-T4) show many abnormalities as adults. These usually include impaired body, pituitary and thyroid growth, diminished pituitary and serum TSH concentrations, a diminished serum T4 and a diminished response to PTU challenge and to thyrotropin-releasing hormone (TRH) stimulation. Experiments are presented which show that these rats are hypersensitive to feedback regulation by T4 in a manner similar to that seen after bilateral anterior hypothalamic lesions. They show a subnormal response to PTU challenge and an excessive suppression of serum TSH and goiter growth after T4. Pituitary TSH was less depleted in neo-T4 rats when a small dose of T4 was given daily with PTU and pituitary TSH was more sensitive to suppression by a larger dose of T4 in the neo-T4 group. There was an impaired rebound increase in pituitary TSH following a single inhibitory dose of T4 injected into the adult hypothyroid rat. Although the hypothalamic TRH content is increased in the neo-T4 rat, the circulating concentration of TRH was found to be significantly decreased, supporting the theory that the defects observed in the neo-T4 rat may be the consequence of an impaired hypothalamic secretion of TRH.

Endocrine studies of the untreated progeny of thyroidectomized rats

Experiments were conducted to assess late and persistent endocrine changes in the progeny of rats born and/or nursed by thyroidectomized (Tx) dams. Forty-five female rats were radiothyroidectomized several weeks before mating with normal males, and compared with the progeny of 26 control females. In all, 248 progeny were studied when adult. Tx dams had significantly reduced fertility (87% of controls), increased pup (11% versus 0) and maternal mortality (27% versus 0), and smaller litters (6.5 versus 11.8 pups/litter). It was shown that the offspring of thyroidectomized female rats had delayed eye opening (15.3 versus 14.3 days), smaller weaning (40.4 versus 54.4 g) and adult body weight (230 versus 260 g), smaller pituitary glands (12.2 versus 14.0 mg), and enlarged thyroid gland (14.2 versus 12.4 mg). Ovarian and testicular weight were decreased (73.9 versus 83.7 mg and 3.2 versus 3.6 g, respectively). The serum thyroid stimulating hormone (TSH) concentrations were increased from 53.8 to 84.4 muU/ml in the males. The pituitary TSH contents were not significantly altered, and the serum TSH response to thyrotropin releasing hormone (TRH) was normal. These persistent effects differed from the late effects of both fetal and neonatal hypothyroidism and neonatal underfeeding. Cross-fostering experiments showed that the diminished weaning weights were the result of the pups being nursed by the hypothyroid dams. The increased nursing mortality and the pituitary and thyroidal changes were the result of prenatal influences produced by the hypothyroid dams, since being nursed by a normal foster dam did not prevent them. The persistently enlarged thyroid glands and the elevated serum TSH in the male offspring of thyroidectomized dams suggested a permanent alteration in the set point of pituitary-thyroid regulation as the consequence of maternal hypothyroidism.

Altered cardiac responsiveness and regulation in the normal cardiac output type of borderlind hlpertension

Of 145 patients with borderline hypertension, 30% had increased resting cardiac index (QI), whereas the remainder had normal values. The specific aim of this study was to investigate cardiac regulation in patients who had normal resting QI. Eighty-five control subjects were used for comparison. At rest, patients with normal QI showed evidence of decreased parasympathetic inhibition; the QI after injection of atropine increased less than in control subjects. After complete cardiac autonomic blockade with propranolol and atropine, QI and stroke volume were significantly lower in patients than in control subjects. The mechanism of this low QI was further analyzed. Central blood volume, which strongly correlates with stroke volume, was used as an estimate of the cardiac venous filling. After blockade, stroke volume was decreased in patients, but central blood volume was normal. Patients also showed a decreased heart rate and QI response to infusion of isoproterenol. It is therefore postulated that two components may be responsible for the low QI in the "denervated" heart: patients exhibit a decreased responsiveness to sympathetic stimulation, and they may also be less responsive to venous filling. Behind the facade of cardiac normality in these borderline hypertensive patients with normal cardiac output, there is evidence of altered autonomic control of the heart (decreased vagal inhibition) and of changed cardiac response to sympathetic stimulation and possibly to venous filling.

Platelet hypersensitivity induced by cholesterol incorporation

Platelets from individuals with familial hypercholesterolemia show increased sensitivity to the aggregating atents, epinephrine and ADP. Since the mechanism of this abnormal sensitivity is unknown, we examined, in vitro, the influence of the plasma lipid environment on the function of platelets. The composition of plasma lipids was altered by the addition of sonicated cholesterol-dipalmitoyl lecithin liposomes which were "cholesterol normal" (cholesterol-phospholipid mole ratio [C/P] equals 1.0, "cholesterol rich" (C/P eauals 2.2), or "cholesterol poor" (C/P equals 0). Cholesterol-normal liposomes had no influence on platelet lipids or platelet function. In contrast, after incubation for 5 h at 37 degrees C with cholesterol-rich liposomes, normal platelets acquired 39.2% excess cholesterol with no change in phospholipids or protein. The percent increase in platelet membrane cholesterol was three-fold that of the granule fraction. The acquisition of cholesterol by platelets was associated with a 35-fold increase in sensitivity to epinephrine-induced aggregation (P less than 0.001) and 15-fold increase to ADP aggregation (P less than 0.001), as determined both by aggregometry and by [13C]serotonin release. Response to thrombin or collagen was unchanged. Platelets incubated with cholesterol-poor liposomes underwent a selective loss of 21.4% cholesterol and this was associated with an 18-fold reduction in their sensitivity to epinephrine. These studies demonstrate that the cholesterol content of platelets is dependent on the lipid composition of the milier. Cholesterol acquired by platelets may exert its effect on platelet function by a modification of the platelet membrane.

Late effects of neonatal undernutrition and overnutrition on pituitary-thyroidal and gonadal function

Neonatal rats were underfed or overfed and then, at weaning, placed on a normal diet and allowed to mature. Although overfed rats were obese at weaning, they were of normal weight when mature. The underfed rats remained smaller all their lives. The endocrine organs did not share in this retardation, and were actually larger in several instances when expressed per 100 g body weight. Underfed rats also had delayed eye-opening, normal puberty and normal estrous cycles. Pituitary, hypothalamic and serum TSH concentrations were normal, or even increased (in the underfed females). The responses to propylthiouracil and to thyrotropin-releasing hormone (TRH) were both normal. Thus the tertiary hypothyroidism reported in underfed rats 16 days old did not persist into adult life. In all comparisons the males had higher serum TSH concentrations than females and usually had a greater response to TRH stimulation. The various persistent endocrine abnormalities resulting from neonatal thyrotoxicosis differ from those seen after neonatal caloric deprivation in all pertinent regards except that both have reduced body weights.

Albumin and creatinine clearances in renal disease

1. The ratio of albumin clearance to creatinine clearance (CA/CC) was determined on 129 occasions in forty patients with a wide variety of renal diseases, both 24 h collections of urine and random mid-morning samples being used. The clearance ratios derived from 24 h urine (24 h CA/CC) and random urine (R CA/CC) were compared with random urine protein concentration, 24 h urine protein excretion and 24 h urine albumin excretion.

2. From these measurements 24 h CA/CC could only be predicted accurately by R CA/CC, particularly when patients with postural proteinuria were excluded.

3. The diurnal variation of CA/CC was investigated in twelve patients with renal disease. The individual values for CA/CC obtained throughout the day were within the limits of prediction of 24 h CA/CC already established. The diurnal variation of CA/CC was considerably less than that of CA or CC alone and also less than that of the rates of protein and albumin excretion.

4. It is suggested that CA/CC is the best readily available measure of ‘glomerular leakiness’ and examples are given of its clinical value. In patients with renal disease 24 h CA/CC could be predicted, in this study, from the clearance ratio based on simultaneous random urine and blood samples.

Late effects of perinatal morphine administration on pituitary-thyroidal and gonadal function

A brief period of neonatal morphine sulfate (MS) addiction in the rat results in lifelong alterations in some endocrine functions. Some changes, such as decreased growth, are probably the nonspecific result of neonatal malnutrition. Others may be the result of altered hypothalamic pituitary function. When neo-MS rats were studied as adults they tended to have larger pituitary glands containing less TSH. Their thyroid glands were larger when corrected for the smaller body weight. Testicular weights were increased and uterine weights were reduced. Adult basal pituitary and serum TSH levels were usually normal, but upon challenge with propylthiouracil, there was an initially greater goiter growth suggesting an initial abnormal increase in TSH secretion followed by a decrease in net TSH synthesis and diminished pituitary size. These late endocrine consequences of neonatal narcotic addiction in rats make it important to study the adult endocrine function of humans born of addicted mothers.

Nicotinic acid as adjuvant therapy in newly admitted schizophrenic patients

A placebo-controlled, comparative clinical study was conducted to test the hypothesis that nicotinic acid as an adjuvant medication has a beneficial therapeutic effect over and above the effect which can be achieved by the administration of phenothiazine drugs alone, over a six-month period, in newly (recently) admitted schizophrenic patients.The most important single finding was that no statistically significant therapeutic difference was seen between the active treatment and the placebo groups; i.e., the addition of nicotinic acid or nicotinamide to the regular phenothiazine treatment regimen did not have any measurable therapeutic effect in this sample of patients. It was shown that patients in the placebo group received a lower total daily amount of phenothiazine drugs than those on either of the active substances. Furthermore, it was noted that the addition of the active substances did not reduce the number of days of hospitalization.

Nicotinic acid in the prevention and treatment of methionine-induced exacerbation of psychopathology in schizophrenics

In this placebo-controlled crossover study nicotinic acid, in a fixed dosage of 3000 mg. a day, produced statistically significant improvement in chronic hospitalized schizophrenic patients. We were able to reproduce the clinical observations and the results of previous workers; that is, the exacerbation of psychopathological symptoms by the combined administration of methionine and tranylcypromine. Nicotinic acid failed to prevent by prior administration or to relieve by subsequent administration, the methionine-tranylcypromine-induced exacerbation of psychopathology. This might have been due to the inadequate dosage of nicotinic acid given but the possibility of a toxic psychosis due to the metabolite, methionine sulfoximine, must be seriously considered.

Urinary steroid pattern in male hypogonadotrophic hypogonadism

During clinical studies on a 34-year-old man with marked hypogonadism secondary to pituitary gonadotrophin insufficiency, an attempt was made to determine whether the testes were capable of androgen production when stimulated by exogenous chorionic gonadotrophin (A.P.L.).Androgen excretion before and after chorionic gonadotrophin administration was studied. Total and fractionated 17-ketosteroid patterns suggested a severe Leydig cell deficiency which was confirmed by testicular biopsy.Panhypopituitarism was considered excluded by a normal response to metyrapone ditartrate, by a normal serum PBI and a normal radioactive iodine uptake. Genetic disorders were likewise excluded to the extent possible by determining that the chromosome pattern was normal and by determining that no similar condition existed in another member of the same family. The association of anosmia with gonadotrophin insufficiency in this case suggests a primary disorder in the hypothalamo-mamillary-tuber cinereum area.