Alteration in glucose homeostasis by the drugs acting on CNS in euglycemic or diabetic patients may pose problems for treating physicians while interpreting the data on blood sugar levels. The problem may be further aggrevated in diabetic patients maintained on antidiabetic agents because this may adversely affect the course of the disease especially in persons on long term therapy with CNS active drugs. Since this is a group of drugs with diverse chemical structure and varied pharmacodynamic/pharmacokinetic properties, no single mechanism can be ascribed in each of the reported cases. This article is an attempt to discuss the available literature and probable mechanisms involved in modification of glucose homeostasis by CNS active agents and their interaction with antidiabetic drugs.

Many of the applications of liposome drug-delivery systems have been limited by their short circulation half-lives as a result of rapid uptake into the reticuloendothelial (mononuclear-phagocyte) system. Different approaches were taken up to formulate liposomes with prolonged circulation half-lives (Stealth liposomes). A brief review of different methods followed to prepare and characterise stealth liposomes is presented in this article. Bilayer compatible polymers such as polyethyleneglycols, gangliosides and glycolipids are used to prepare these liposomes. Of all gangliosides especially GM1 was found to be most effective.

A brief study on the usefulness of a method involving problem solving skills to teach pharmacology to undergraduate medical students is presented. This is based on the publication by Upjohn (USA) on patient oriented problem solving (POPS) method of medical education with slight modification of the details of conducting the session. This study involves one session on hypertension. POPS was used as an adjunct to the lecture session. Pretest and post tests were conducted as a method to determine the improvement in knowledge acquired by the student. Preformed questionnaire was administered to all the students asking for their opinions on the usefulness of the POPS system teaching. The feedback from this batch of students suggests that this method is very useful and interesting.

Attitudes of medical students towards objective structured practical examination (OSPE) were assessed using a standardised Likert scale. Students considered OSPE a good means of practical examination. However, they felt that not all skills are tested by this and that it is physically taxing. Based on these observations, changes have been made in the teaching as well as evaluation methodology so that students attain maximum learning.

Both H1 and H2 blockers were studied for their protective action against histamine aerosol induced bronchospasm in guinea pigs, The H1 blockers produced significant dose dependant complete protection in some animals and significant prolongation of the exposition time in the remaining animals. Diphenhydramine was taken as the standard. The H2 blocker cimetidine also produced the same effects as the H, blockers. When both diphenhydramine and cimetidine were administered together additive effect was produced with highly significant complete protection in some animals and significant prolongation of the exposition times in the remaining animals. This suggests involvement of both H, and H2 receptors in production of histamine induced bronchospasm in guineapigs.

Glycyrrhizin a triterpeniod glycoside obtained from Glycyrrhiza glabra Linn., was tested against some RNA (Chandipura, Measles, Polio vaccine type 1,2 and 3, Polio wild type 1,2 and 3) and DNA (Herpes type 1 and 2) viruses. It inhibited plaque formation for HSV-1 and HSV-2 at a concentration of 0.606 mM. However with Chandipura, measles and polio types 1, 2 and 3 of both the wild and the Sabin's vaccine strains, same effect could be obtained at a concentration of 1.216mM. The minimal inhibitory concentrations were not toxic to Vero (African Green Monkey kidney) and HeLa (Human Cervical carcinoma) cell lines.

A rapid and simple high performance liquid chromatography (HPLC) method for estimating triclabendazole and its metabolites in plasma was developed. The method was applied to determine the pharmacokinetics of intraruminally administered triclabendazoie in sheep and goat. The parameters Cmax Tmax AUC and t1/2 were similar in both the species.

Ten peptides related to the p-receptor agonist, dermorphin (Tyr-D-Ala-Phe-Gly-Tyr-Pro-Ser-NH2,) having structural modifications at positions 2,3.4 and 7 were synthesised by the solid phase method by using 9- fluorenylmethyloxycarbonyl (Fmoc)- amino acid trichlorophenyl (Tcp) ester as coupling agents and Merrifield resin as the solid support and their biological activities namely the effect on guinea pig ileum, the analgesic and the antidiarrhoeal activity were studied. The synthetic peptides were found to possess more antidiarrhoeal activity than any other activity and this is most pronounced in the analogues, (D- Met(O)2, MePhe3, Sar4, Tyr7) dermorphin and (D-Met(O)2 MePhe3, Sar4, Thr7) dermorphin.

Time dependent protective effects of selenium or zincsupplementation during mercury exposure was investigated in female rats. Concomitant exposure to selenium or zinc during 3 days of mercury administration prevented most of the mercury induced clinical and biochemical indices of renal toxicity. Mercury contents of kidneys were also less marked in animals administered mercury and selenium as observed on day 4. However, it increased significantly in blood while, remained unchanged in hepatic tissue. Following cessation of selenium supplementation, toxic effects of mercury reappeared on day 8. The results suggest that selenium administration reduces the renal toxicity of mercury. Zinc seems to have no preventive value against mercury.

A protective effect of vitamin E against cytotoxic antitumor drugs (cyclophosphamide, methotrexate, 5-fluorouracil; CMF) induced damages of rat small intestine was studied. Vitamin E protects the brush border membranes (BBM) from CMF induced lipid peroxidative damages. Intestinal brush border membrane bound sucrase, maltase and alkaline phosphatase were restored by co- administration of vitamin E with CMF. Vitamin E co-administration decreased TBA reacting substances (TBARS) levels and increased the level of sulfhydryl containing membrane proteins. Cholesterol and phospholipid levels which were altered in CMF treated rats were found to be restored by co-administration of vitamin E. The results are discussed with reference to the effect of vitamin E on TBARS, SH groups, membrane bound enzymes and membrane lipid composition.

The effect of adrenocorticosteroids on imioramine (IMA) analgesia was evaluated in sham-adrenalectomised (sham-ADX) and adrknalectomised (ADX) rats using tail-flick test. Adrenalectomised rats displayed greater sensitivityto IMA(5-20 mg/kg, i.p.) induced analgesia. Subcutaneous administration of glucocorticoids,. corticosterone -(0.01-10 mg/kg), hydrocortisone (0.5 mg/kg), dexamethasone (0.5 mg/kg), attenuated the analgesic effect of IMA (20 mg/kg) in sham-ADX or ADX rats. Mineralocorticoid, aldosterone (0.5-10 mg/kg), had no effect, Adrenalectomy per se or adrenocorticosteroids per se did not alter the basal tail-flick reaction latency. Thus the enhanced potency of IMA in ADX rats may be mediated by the absence of circulating adrenocorticosteroids.

The mechanisms of action of calcium channel antagonists in producing hyperglycaemia was studied in rats, liyperglycaemic effect was found to be mainly due to reduced insulin release and its effect on overall glucose uptake by peripheral tissues. There was a significant fall in uptake of glucose by the diaphragm and skeletal muscle of the thigh while a rise in glycogen content in the liver. Serum insulin level was lowered significantly and the results were similar with all the three calcium channel antagonists studied. It is possible that glycogenesis in the liver limits the hypergfycaemic effect within physiological limit.

Adult male rabbits injected with alloxan (50 mg/kg, i.p.) were divided into two groups of nine each. One group received placebo and the other group an aqueous suspension of D-400, at the dose of 1gm/kg body weight orally daily for 36 weeks. Blood glucose, blood urea and serum creatinine were estimated initially and at every 6-weekly intervals. At the end of 36 weeks D-400 significantly prevented the rise in blood urea and serum creatinine levels as compared to the control. Although a rise in blood sugar was noticed in both the groups, the level of blood sugar after 36 weeks was significantly lower in the D-400 treated group. This shows the favourable response of D-400 against alloxan-induced renal damaae and hyperglycaeima.

A series of nitrophenyl 4,4,6 trimethyl, 1 H, 4H pyrimidine 2 thiols (NPTP) were synthesised and tested for their anticonvulsant activity in mice against maximal electro shock and metrazol (MET) induced convulsions. Test compounds were given in graded doses (20,40,60,80 mg/Kg i.p.) and compared with phenobarbitone as a standard control. The protection produced by the test compounds was dose dependent. Phenobarbitone, produced 100% protection in the dose of 50 mg/Kg, whereas test compounds exhibited the same effect with 80 mg/Kg except 2 NPTP against MET induced convulsions.

A series of nitrophenyl 4,4,6 trimethyl, 1 H, 4H pyrimidine 2 thiols (NPTP) were synthesised and tested for their anticonvulsant activity in mice against maximal electro shock and metrazol (MET) induced convulsions. Test compounds were given in graded doses (20,40,60,80 mg/Kg i.p.) and compared with phenobarbitone as a standard control. The protection produced by the test compounds was dose dependent. Phenobarbitone, produced 100% protection in the dose of 50 mg/Kg, whereas test compounds exhibited the same effect with 80 mg/Kg except 2 NPTP against MET induced convulsions.