Pharmacological actions of Pongamia pinnata seeds--a preliminary study.

Direct ethanolic and sequential petroleum ether, chloroform, acetone and ethanolic extracts (50-100 mg/kg, i.p.) of P. pinnata seeds given 30-60 min before revealed anti-inflammatory, analgesic and anti-ulcerogenic activities in rats. The activities were present maximum in petroleum ether and chloroform extracts. However, the extracts also showed shortening of pentobarbitone induced 'sleep time' in rats.

Comparative effects of mast cell degranulators on perfused systemic blood vessels of Bufo melanostictus and Rana tigrina.

Three agents known to induce release of mast cell constituents, viz. polymyxin, compound 48/80 and polysorbate-80, were evaluated for effect on perfused blood vessels of R. tigrina and B. melanostictus. The mast cell degranulators caused vasoconstriction in frog and toad, except that for P-80 whose responses in toad were equivocal. Toads showed a general low responsiveness in comparison to frogs. Pharmacologic intervention with pheniramine, metergoline, hydergine, atropine and mecamylamine, respectively ruled out role of histamine, 5-HT, catecholamine or acetylcholine or even autonomic mechanisms in the above phenomena. The observations are suggestive of phylogenetic differences in biochemical profile of mast cells in amphibian species.

Receptor mechanisms in vasoconstrictor responses to choline esters in Bufo melanostictus.

Choline esters have been found to cause vasoconstriction of perfused systemic blood vessels of common Indian toad, Bufo melanostictus. The vasoconstriction appears to be mediated through atropine sensitive receptors and nicotinic mechanisms appear unlikely to be involved.

Some aspects of vascular pharmacology of frog (Rana tigrina).

Vascular autonomic receptors in amphibians exhibit difference from more evolved mammalian species. Vascular perfusion studies in frog indicate constrictions by prominent muscarinic but rudimentary nicotinic constrictive regulation by cholinergic systems. Difference from classical effect-patterns of pharmacological interventions, observed in the study, make room to visualise complexity of additional regulatory mechanisms.

Blood histaminase in phlyctenulosis.

Blood Histaminase estimations were done in 42 cases of phlyctenulosis and 25 normal subjects. Significantly higher level of blood Histaminase was found in patients of phlyctenulosis, which may be a consequence of its induction secondary to increased release of histamine in the early phase of disease.

Immunopharmacological studies on Picrorhiza kurroa Royle ex Benth. Part VI: Effect on anaphylactic activation events in rat peritoneal mast cells.

Mechanism of inhibition of mast cell anaphylaxis by P. kurroa-extract (PK) treatment in rats was investigated. Mast cell-IgE binding, assessed from induction of passive sensitization, was not affected. Calcium-independent early activation events in mast cell anaphylaxis indicated on inhibitory influence of PK-treatment. Inhibition of membrane-protease release by PK-treatment was suggested by study of gastric secretion and exhibition of saturable synergism with Di-isopropyl fluoro phosphate on inhibition of anaphylactic degranulation. pH-independence of mast cell stabilizing effect negates any PK-influence on phospholipid transmethylation. The results complement findings of earlier studies on indirect effects of PK through alteration of membrane structure/function.

Bioflavonoids and vasoactive mediator release from mast cells.

5-hydroxy and 7-hydroxy flavones significantly attenuated the carrageenin-induced pedal inflammation in rats; however, the anti-inflammatory effect declined at higher doses. These compounds produced positive inotropic effect on frog atria, which exhibited tachyphylaxis and was selectively abolished by indomethacin pretreatment. Studies on the rat mesenteric mast cells revealed that both the compounds, administered either in vitro or in vivo, induced a significant degree of mast cell degranulation in higher concentrations/doses. The mast cell degranulation induced by compound 48/80 was, however, prevented by lower, but not higher, concentrations/doses of the flavones. Local injection of 7-hydroxy flavone into the hind paw of rat showed that, in higher doses, the compound produced significant oedema. It was concluded that these compounds have a biphasic action: mast cell stabilisation and degranulation at lower and higher concentrations/doses, respectively.

Production of myocardial lesions in a graded fashion by noninvasive technique in albino rats.

Systematic study of producing graded lesions of myocardium with the use of Isoproterenol (IPT) reveals that mild to severe degree of infarction can be induced by administering the compound for one to four consecutive days in the dose of 85 mg/kg body weight in rats. These findings differ slightly from those of Rona et al. where they have not attempted to produce the lesions in a graded fashion. The experimental period can be reduced to two days by using high dose (170 mg/kg), but such procedure increases significantly the mortality in these animals and lesions are not produced in graded fashion.

Antispasmodic activity of the tertiary base of Daucus carota, Linn. seeds.

A nitrogen containing base responding to Mayer's test and Dragendorff's reagent for tertiary bases has been isolated from the seeds of Daucus carota Linn. The effects of the base as its bromide have been studied on smooth muscles of ileum, uterus, blood vessels and trachea of different species of animals. The tertiary base has been found to have papaverine like nonspecific smooth muscle relaxant and spasmolytic activity, but its activity was found to be about one-tenth of that of papaverine.