Hypotensive and vasorelaxant effects of ethanolic extract from Jatropha gossypiifolia L. in rats.

The present work was carried out to examine the hypotensive effects of ethanolic extract (EE) from Jatropha gossypiifolia L. The oral administration of EE (125 or 250 mg kg(-1) day(-1)) caused a significant and dose-dependent reduction of the systolic blood pressure. The concentration-response curves to norepinephrine (NE) or Ca(2+) were non-parallelly shifted to the right and the maximum contractile responses were concentration dependently depressed by EE (0.1 or 0.5 mg/ml) in endothelium-deprived mesenteric artery. The cumulative additions of EE (0.1-30 mg/ml) caused a concentration-dependent relaxant response in endothelium-deprived mesenteric artery precontracted with NE or Ca(2+). In conclusion, our results have shown that the EE from J. gossypiifolia L. can elicit hypotension, by oral via, in conscious normotensive rats and vasorelaxant activity on rat mesenteric rings precontracted with NE or Ca(2+).

Analgesic activity of a triterpene isolated from Scoparia dulcis L. (vassourinha)

Analgesic and anti-inflammatory activities of water (WE) and ethanolic (EE) extracts of Scoparia dulcis L. were investigated in rats and mice, and compared to the effects induced by Glutinol, a triterpene isolated by purification of EE. Oral adminsitration (p.o.) of either WE or EE (up to 2 g/Kg) did not alter the normal spontaneous activity of mice and rats. The sleeping time induced by sodium pentobarbital (50 mg/Kg, i.p.) was prolonged by 2 fold in mice pretreated with 0.5 g/Kg EE, p.o. Neither extract altered the tail flick response of mice in immersion test, but previous administration of EE (0.5 g/Kg, p.o.) reduced writhings induced by 0.8% acetic acid (0.1 ml/10 g, i.p.) in mice by 47% EE (0.5 and 1 g/Kg, p.o.) inhibited the paw edema induced by carrageenan in rats by respectively 46% and 58% after 2 h, being ineffective on the paw edema induced by dextran. No significant analgesic or anti-edema effects were detected in animals pretreated with WE (1 g/Kg, p.o.). Administration of Glutinol (30 mg/Kg, p.o.) reduced writhing induced by acetic acid in mice by 40% and the carrageenan induced paw edema in rats by 73%. The results indicate that the analgesic activity of S dulcis L. may be explained by explained by an anti-inflammatory activity probably related to the triterpene Glutinol.