Résumé
The gastroprotective action of the aqueous extract (AE) and the hydroalcoholic extract obtained from the leaves of Struthanthus marginatus (Desr.) Blume, Loranthaceae, were performed with in vivo models in rodents using: ethanol, indomethacin or stress-induced ulcers, determination of gastric secretion and the mucus production. The scavenger activity of AE in vitro was tested by the DPPH method. The treatment with the extracts (125-1000 mg/kg) significantly inhibited ulcerative lesions in comparison with the negative control groups in all the models evaluated and demonstrated greater effectiveness of the aqueous extract. Regarding the model of gastric secretion, a reduction in volume of gastric juice and total acidity was observed, as well as an increase in the gastric pH. The treatment of rats raised the gastric mucus production. Significant DPPH scavenging activity was evident in the AE. No sign of toxicity was observed. These results show that S. marginatus possesses gastroprotective activity. There are indications that the mechanisms involved in anti-ulcer activity are related to a decrease in acid secretion and an increase in gastric mucus content. Also, there is evidence for the involvement of antioxidant activity in the gastroprotective mechanism.