Psychoactive drugs, pineal gland and affective disorders

The possibility of pineal gland involvement as a part of "neuroendocrine dysfunction" in some of the psychiatric diseases has received special attention in recent years. The discovery of a cascade of receptors and the action of many psychoactive drugs on pineal gland supports the concept that the pineal gland can be considered as a suitable model system for assessing the action of psychotropic drugs. Psychotropic drugs, particularly antidepressants both tricyclics and monoamine oxidase inhibitors when administered either to animals or to patients suffering from depressive illness affects the pineal gland function and melatonin concentration. This raises the possibility that the beneficial effects of these drugs may relate to their ability to alter the pineal gland function and melatonin secretion. The occurrence of seasonal affective disorders and their response to bright light treatment implicate, melatonin as a "bio-chemical marker" for these disease states. In view of these facts it can be suggested that pineal gland does play an important role in the etiology of mental diseases, especially affective disorders.

Hookworm infection in a rural community in south India and its association with haemoglobin levels

Faecal samples were obtained from 1113 persons living in a rural area in South India, and the hookworm ova load (Necator americanus) was determined using Kato's thick smear method. Evidence of hookworm infection was present in 92%, 77% having a count of under 100 epg, 11% a count of 1000 to 1999 epg, and 4% having counts between 2000 and 12,000 epg. Females had significantly higher ova counts than males on the average, but age did not appear to have any effect. Haemoglobin was also estimated: 80% of adult males, 87% of adult females and 90% of children were anaemic. There was a significant negative association between ova load and haemoglobin level, and the decrease in haemoglobin for a doubling of the ova load was estimated by regression analysis to be 0.18, 0.29 and 0.16 g/dl in adult males, adult females and children, respectively. There was nearly perfect agreement in the ranking of 10 clusters by mean ova count and mean haemoglobin level or percentage with anaemia.

The effect of vagotomy and hydrocortisone administration on pulmonary surfactant activity in adult albino rats

The role of vagus and hydrocortisone in the regulation of lung surfactant was studied in adult albino rats. Dynamic surface tension and phospholipid content were measured in the lung wash for estimating surfactant activity. The results indicate that vagotomy significantly decreases the surfactant activity whereas hydrocortisone does not alter it. But when hydrocortisone was administered prior to vagotomy it could prevent the decrease in surfactant activity. Thus it is concluded the regulation of lung surfactant in the adult lung is mainly by vagus nerve and hydrocortisone as such has no role but in the absence of vagal regulation hydrocortisone could maintain normal lung surfactant activity.

Suppression of delayed-type hypersensitivity to oxazolone in whole-body-irradiated mice and protection by WR-2721

The effect of whole-body irradiation on cellular immunity, as measured in vivo by delayed-type hypersensitivity (DTH) to oxazolone (4- ethoxymethylene -2-phenyl- oxazol -5-one), was determined in CD2F1 mice. DTH, determined by changes in ear swelling after challenge with oxazolone, was significantly depressed in irradiated mice (500-900 rad of 60Co) in a dose-dependent fashion when animals were irradiated after sensitization and before challenge with oxazolone. Administration of WR-2721 [S-2-(3-aminopropylamino)ethylphosphorothioic acid] 30 min before irradiation (2 days after sensitization) resulted in protection against suppression of DTH, which was dependent on drug and radiation dose. An effective dose of WR-2721 (200 mg/kg body wt) provided an approximate dose-modifying factor of 1.3. The data suggest that WR-2721 interacts with cells involved in that DTH response (lymphocytes and/or macrophages) and that WR-2721 may be useful in protecting against radiation-induced decrements in cell-mediated immunity.

Intrapericardial instillation of sodium hydroxide: failure to produce pericardial symphysis

Previously reported clinical studies have suggested sodium hydroxide as an effective agent in causing pleural symphysis. To explore the sclerosing potential of this agent, we instilled 0.5% sodium hydroxide into the pericardium of four dogs. Normal saline was instilled into the pericardium of one control dog. Echocardiograms, 24 hour EKG monitoring and intracardiac pressures were recorded. One dog was sacrificed at the end of 24 hours, another at the end of seven days and three other dogs were sacrificed at the end of 28 days. ST elevations and prolonged episodes of supra-ventricular and ventricular tachycardia were noted during and within 24 hours after the intrapericardial instillation of sodium hydroxide in all the dogs. No arrhythmias were noted in the control dog. None of the dogs showed pericardial symphysis. These results suggest that sodium hydroxide causes serious cardiac arrhythmias when instilled intrapericardially and is of limited value in causing pericardial symphysis.

Depression in hypertensive subjects

168 patients attending hypertension clinic were randomly selected for the study. They were thoroughly investigated using E.C.G., X-ray chest, Urine analysis, Blood sugar, Blood urea, Serum cholesterol, Serum K, Serum Na, Scrum creatinine and Uric acid level. Detailed psychiatric case history and mental examination was carried out. Beck Rating Scale was used to measure the depression. 25% of hypertensive subjects exhibited depressive features and their mean score in Beck Rating scale is 21.76. The mean score of non-depressives is 4.46. All patients were receiving methyl dopa.25 mg. twice or thrice daily with thiazide diuretic. No significant difference in the incidence of depression with the duration of medication was observed.The hypertension was classified into mild, moderate and severe depending on the diastolic pressure. Depression was more frequent in severe hypertensives but not to the statistically significant level.Further hypertensives were classified into:1. Hypertension without organ involvement2. Hypertension with LVH only3. Hypertension with additional organ involvement4. Malignant hypertensionDepression was significantly more frequent in hypertensives with complications and also hypertensives in whom the B.P. remained uncontrolled. As all the patients were on the same drug, the drug effect is common to all; hence, the higher incidence of depression in hypertensives with complications is due to the limitation and distress caused by the illness.

Urinary melatonin in depression

This report is based on a study of 12 cases of depression (8 endogenous, 4 neurotic) with a view to explore the possible association between urinary melatonin and the illness prior to and following treatment. While cases of endogenous depression had low 24 hour as well as nocturnal urinary melatonin levels, the neurotic depressives showed higher than normal levels. A rise in the 24 hour melatonin levels occurred in all cases of endogenous depression though this did not apply, to the nocturnal levels. An association between melatonin levels with suicide behaviour, insomnia, psychomotor retardation and diurnal variation is discussed.

A model for memory

A model for memory based on ideas of non-equilibrium phase transitions is proposed. This model postulates the existence of external stimulus maintained memory. Some experiments which support this model are compared with the predictions of this model.

Effect of cowdung smoke inhalation on E.C.G. of rats

The present study was conducted on 20 adult albino rats divided into group I (n = 10) and group II (n = 10). Group I animals were exposed to cowdung smoke for 60 min twice a day for a period of 75 days whereas group II served as control. ECG of control rats was essentially similar to that of man. ST segment was absent, Q wave absent or rudimentary and the mean QRS axis + 45 degrees. Rats exposed to cowdung smoke revealed a significant increase in PR interval and a mean QRS of + 117.5 degrees. Our results indicate that inhalation of cowdung smoke leads to conduction defects and right axis deviation.