RESUMO
This study investigates the effects of an ethanolic extract from the stem bark of Combretum leprosum Mart. & Eiche (Combretaceae) on experimental ulcers induced by ethanol and indomethacin and on gastric secretion and mucus content in pylorus-ligated rats. The effects were compared with those of ranitidine and carbenoxolone. Combretum leprosum orally administered elicited a complete inhibition of the appearance of gastric lesions induced by ethanol and a partial reduction when indomethacin was used as an ulcerogenic agent. Moreover, the protection against gastric ulceration induced by ethanol was decreased with indomethacin pretreatment. The intraduodenal administration of Combretum leprosum in four-hour pylorus-ligated rats increased the volume and pH of gastric juice while decreasing the acid output and produced a significant increase in gastric wall mucus content. The major compounds detected in a preliminary phytochemical screening were triterpenes, flavonoids, taninns and saponins. This study provides evidence that the ethanolic extract of Combretum leprosum possesses gastroprotective and anti-ulcerogenic effects, which are related to the inhibition of the gastric acid secretion and an increase of mucosal defensive factors such as mucus and prostaglandin.
Assuntos
Antiulcerosos , Combretum/química , Úlcera Gástrica/induzido quimicamente , Úlcera Gástrica/prevenção & controle , Animais , Anti-Inflamatórios não Esteroides , Etanol , Ácido Gástrico/metabolismo , Mucosa Gástrica/efeitos dos fármacos , Mucosa Gástrica/metabolismo , Indometacina , Masculino , Muco/metabolismo , Casca de Planta/química , Extratos Vegetais , Caules de Planta/química , Ratos , Ratos Wistar , SolventesRESUMO
Literature report is lacking on pharmacological studies of the plant Heteropterys aphrodisiaca, endemic to the scrublands of Brazil. The present study was carried out to investigate the effects of oral dosing with extract BST0298 from this plant, on learning and on memory, in young (3-6-month-old) and aged (20-28-month-old) rats. The aged animals presented significant memory deficits in both the passive avoidance and T-maze left/right discrimination tests. Treatment for 7 days (50 mg/kg) or 26 days (100 mg/kg) with extract BST0298 restored the memory deficits in the passive avoidance test. However, no improvement in memory was observed after acute administration of extract BST0298 (100 mg/kg) in aged rats. An improvement in learning was also observed in the left/right discrimination test in aged rats treated for 109 days with BST0298 at a dose of 50 mg/kg. These results suggest that treatment for 7 days or more with H. aphrodisiaca improves learning and memory deficits in aged rats.