Anti-inflammatory and diuretic activity of a new class of compounds--Schiff bases of 3-amino-2-methylquinazolin 4(3H)-ones.

Eighteen Schiff Bases of 3-amino-2-methylquinazolin-4(3H)-ones were synthesised and screened for anti-inflammatory and diuretic activity. Anti-inflammatory activity was identified in PNG-1, PNG-13, PNG-14, PNG-15 and PNG-17.

Antiallergic activity of alkyl substituted pyrazolo[3, 4-d]pyrimidine (compound 88-765).

Compound 88-765 (4-amino-6-methylthio-1-(2', 2'-diethoxyethyl)-1 H-pyrazolo[3, 4-d]pyrimidine) has shown potent antiallergic activity in experimental models. The compound inhibited the passive cutaneous anaphylaxis (PCA) reaction in rats in dose-dependent manner (5-100 mg/kg, po) by 47 to 87%. In mice it inhibited PCA by 78% at 50 mg/kg, po. It also inhibited mast cell degranulation of normal and passively sensitised rats induced by compound 48/80 and egg albumin, respectively. These effects of Compound 88-765 were comparable with that of disodium cromoglycate (DSCG). The results suggest that compound 88-765 possesses potent antiallergic activity.

Prevention of ischaemia-induced biochemical changes by curcumin & quinidine in the cat heart.

Effect of myocardial ischaemia on the bioantioxidants levels in the cat heart was evaluated. In addition, effect of curcumin, an anti-inflammatory and anti-thrombotic drug, and quinidine, a standard antiarrhythmic drug, was also studied in the cat. Myocardial ischaemia was induced by the ligation of left descending coronary artery. Quinidine (1 mg/kg, iv) was administered 15 min prior to while curcumin (100 mg/kg, ip) was given 30 min before ligation. Hearts were removed 4 h post coronary artery ligation. Levels of glutathione (GSH), malonaldelhyde (MDA), myeloperoxidase (MPO), superoxide dismutase (SOD), catalase (CAT) and lactate dehydrogenase (LDH) were estimated in the ischaemic and non-ischaemic zones. Both the drugs protected the animals against decrease in the heart rate and blood pressure following ischaemia. In the ischaemic zone, after 4 h of ligation, an increase in the level of MDA and activities of MPO and SOD (cytosolic fraction) were observed. Quinidine and curcumin pretreatment prevented the ischaemia-induced elevation in MDA contents and LDH release. Curcumin pretreatment did not prevent the increase in MPO activity while quinidine did. Results obtained indicate alterations in the bioantioxidants following ischaemia and both curcumin and quinidine prevented ischaemia induced changes in the cat heart.

Platelet functions & lipid profile within 24 hours following an attack of TIA, thrombotic & haemorrhagic stroke.

The present study was undertaken to evaluate comparatively the lipid profile and platelet functions within 24 h of the three most frequent types of stroke encountered in clinical practice. Twenty patients of transient ischaemic attacks, 22 of thrombotic stroke and 26 of haemorrhagic stroke (hypertensive putaminal haemorrhage), all within 24 h of the acute event, and 21 control subjects were studied. Spontaneous platelet aggregation, platelet aggregation induced with adenosine diphosphate (2.5, 3.75 and 5.0 microM) and lipid profile (serum cholesterol, triglycerides, high density lipoprotein, low density lipoprotein and very low density lipoprotein) estimations were performed in all the subjects. Mean platelet aggregation values were significantly lower in haemorrhagic stroke patients as compared to controls. Serum cholesterol, triglycerides and very low density lipoprotein levels in ischaemic groups i.e., transient ischaemic attacks and thrombotic stroke patients, were significantly elevated, more so in the former group. It appears that platelet hypofunction has a role in the pathogenesis of hypertensive putaminal haemorrhage while in patients of transient ischaemic attack and thrombotic stroke, lipids may be a contributing factor in cerebral atherogenesis.

Bioactivity of marine organisms: Part VII--Effect of seaweed extract on central nervous system.

Alcohol extracts of marine algae (Rhodophyceae, Phaeophyceae and Chlorophyceae) were screened for their effect on central nervous system. Of 69 species investigated 8 appeared biologically active, 6 being CNS stimulant and two depressant, sites and dates of collection are given.

Platelet functions and lipid profile in haemorrhagic and thrombotic stroke patients.

The present study was conducted in 17 patients of haemorrhagic stroke (HS), 19 patients of thrombotic stroke (TS) and 14 control subjects. In each subject platelet functions (spontaneous platelet aggregation (SPA), aggregation induced with 10, 5, 2.5 microM ADP and 10 micrograms/ml of collagen) and complete lipid profile (total cholesterol, triglycerides, high density lipoprotein [HDL], low density lipoprotein [LDL], very low density lipoprotein [VLDL] and LDL/HDL ratio) were performed within 7 days of onset of stroke. Platelet aggregation with 2.5 microM ADP was significantly lower (P < 0.05), in both the stroke groups in comparison to controls. No other changes were significant. Mean serum triglycerides and VLDL of TS group were significantly higher than that of controls. Mean LDL/HDL ratio of the same group was significantly lower than HS group. It can be concluded that alterations in platelet functions and lipid profile are induced by both types of strokes in acute stage.

Effect of anti-platelet therapy (aspirin + pentoxiphylline) on plasma lipids in patients of ischaemic stroke.

Twenty-one patients of ischaemic stroke were put on prolonged administration of antiplatelet drugs (aspirin 320 mg once daily with pentoxiphylline 400 mg thrice daily). The serum lipids along with other biochemical parameters were estimated before starting the treatment and after completion of 2 months of therapy. No significant changes were observed in any of the biochemical parameters including lipid profile except in serum high density lipoprotein (HDL) which increased significantly (< 0.05) after 2 months therapy. It is concluded that 2 months antiplatelet therapy has no adverse metabolic effect in patients of ischaemic stroke and the raised serum HDL may contribute to cerebral protective effect.

Bioactivity of marine organisms: Part VI--Screening of some marine flora from Indian coasts.

Alcoholic extracts of 50 botanically identified species of marine flora have been screened for a wide range of biological activities. Of these, 2 extracts exhibited anti-amoebic and antiviral activity each, 3 of them had anti-implantation activity; 9 had hypoglycaemic activity while hypotensive activity was associated with 11 extracts; 14 extracts were found to be diuretic and 1 of them had anti-inflammatory activity. Further, 10 of these extracts exhibited 2 types of activities while a combination of 3 and 4 types of activities was observed in one extract each. Follow-up studies have been carried out in some plants with confirmed activity. The active principles and results of these studies are reported.

Antihistaminic activity of quinethindole: a 2-substituted pyrazinopyridoindole derivative.

Quinethindole, a 2-substituted pyrazinopyridoindole, showed specific antihistaminic (H1) activity in various in vivo and in vitro test models. It also inhibited antigen-induced contraction of ileum of sensitized guinea pig. The antihistaminic activity was of competitive nature.

Effect of centbucridine & lignocaine on biochemical changes in isoproterenol induced ischemia in rats.

Effect of lignocaine and centbucridine against isoproterenol-induced biochemical changes was studied in the rat. Isoproterenol (40 mg/kg twice) increased the heart weight, level of manolaldehyde (MDA) and activity of acid phosphatase, but decreased the myocardial phospholipid content at 48 h. In addition, increase in plasma triglyceride, cholesterol, MDA and creatine phosphokinase activity was observed. Pretreatment of the animals with lignocaine (10 mg/kg) or centbucridine (1, 3 and 10 mg/kg) protected the animals against these biochemical changes. However, increase in heart weight consequent to isoproterenol treatment could not be prevented. Total protection against creatine phosphokinase release in the blood was also not observed. The results suggest that the two drugs inhibit lipolysis. They may also inhibit phospholipases leading to protection against ischemia-induced changes in the rat.

Protective effect of coleonol on biochemical changes produced in coronary ligation induced ischemia.

Coleonol, a diterpine prevented biochemical changes induced by coronary artery ligation in rabbits at a dose of 10 mg/kg, iv. It increased the heart mitochondrial oxygen uptake and O ratio, which may be responsible for the stabilization of heart membrane. The decrease in serum creatine phosphokinase, glutamate oxaloacetate transaminase, glutamate pyruvate transaminase phospholipase and lipid peroxide and increase in cytochrome P450, glycogen and superoxide dismutase activity by coleonol treatment could have contributed to restore myocardial integrity and cardiac function disturbed by coronary artery ligation. The cardioprotective activity of coleonol was found to be comparable to propranolol.

Screening of Indian plants for biological activity: Part XIV.

Alcoholic extracts of 300 botanically identified plant materials from 275 plant species have been tested for various biological activities including chemotherapeutic and pharmacological screenings. Biological activities have been observed in 111 extracts. Follow-up studies have been carried out in some plants with confirmed activity. The active principles and results of these studies are reported.

Adaptogenic activity of Indian Panax pseudoginseng.

The crude extract and saponins of Indian pseudoginseng and saponins of Korean ginseng have been studied using a battery of biological tests in rats and mice. Indian pseudoginseng saponins were found to exhibit better activity than the Korean ginseng saponins in several tests employed. The results indicate a need for in-depth study of Indian pseudoginseng as an adaptogenic agent, after cultivation of the plant under controlled conditions.