ABSTRACT
The antispasmodic effects of acqueous extracts (AE) and tinctures (T) of Aloysia polystachya (Griseb.) Moldenke and Aloysia gratissima (Gillies & Hook.) Tronc., Verbenaceae, were studied on rat isolated ileum and duodenum. These plants are used for gastrointestinal disorders and as eupeptic in South America. Both AE non-competitively inhibited the dose-response curves (DRC) of ACh and the DRC of Ca2+ in high-[K+]o, as well as the T. The T of A. polystachya and A. gratissima respectively inhibited the ACh-DRC at the IC50 of 3.15±0.57 and 6.46±2.28 mg leaves/mL. The Ca2+- antagonist activity of both T occurred with IC50 respectively similar to those of the ACh-DRC, and was potentiated by the depolarization produced by 10 mM TEA, a blocker of K+- channels. The spasmolytic effect of T does not involve DA release and binding to D2, since it was not reduced by 10 µ M metoclopramide. Also, T induced dose-dependent relaxation on the tonic contracture produced by high -[K+]o and ACh. By TLC there were detected in the leaves the presence of carvone, and flavonoids such as quercetin and hesperidin. By HPLC there were not found vitexin nor isovitexin, identified in A. citriodora. The monoterpene (-)- carvone non-competitively inhibited the ACh-DRC (pD'2 of 4.0±0.1) and the DRC of Ca2+ (pD'2 of 3.86±0.19), suggesting that the Ca2+- influx blockade is the mechanism of its antispasmodic effect. Results suggest that the antispasmodic effect of A. polystachya and A. gratissima are mostly explained by the non-competitive blockade of Ca+2 influx. It could be associated to the presence of flavonoids, and in the tinctures to some spasmolytic components of the essential oil such as carvone.
ABSTRACT
The anti-inflammatory activity of the petroleum ether, dichloromethane and methanol extracts from Heterotheca subaxillaris var. latifolia were assayed using 12-O-tetradecanoyl phorbol acetate (TPA) induced ear edema test in mice and carrageenan-induced paw edema test in rats. The dichloromethane extract showed a significant anti-inflammatory activity (91 percent of inhibition) in TPA-induced ear edema test (topical administration at 1 mg/ear). No effects were seen on carragenan-induced edema. Bio-guided fractionation deal to the isolation of the major flavonoids santin, pectolinaringenin, 3,6-dimethoxy-5,7,4'-trihydroxyflavone and hispidulin present in the active fractions.
A atividade antiinflamatória de extratos éter petróleo, diclorometânico e metanólico de Heterotheca subaxillaris var. latifolia, foi testada pelo método de edema induzido pelo 12-O-tetradecanoil phorbol acetato (TPA) na orelha do camundongos e pelo método do edema de pata induzido por carragenina em ratos. O extrato diclorometânico mostrou atividade antiinflamatória significativa (91 por cento inibição) no edema de orelha induzido por TPA (administração tópica de 1 mg/orelha). Não houve efeitos significativos no teste do edema induzido pela carragenina. O fracionamento bioguiado das frações ativas levou ao isolamento dos flavonoides majoritários santina, pectolinaringenina, 3,6-dimetoxi-5, 7,4 '-trihidroxiflavona e hispidulina.