RESUMO
AIM OF THE STUDY: Vochysia tucanorum is an important medicinal plant used in the Cerrado of Brazil against gastric disorders and this study reveals the pharmacological action of this traditional medicine use. MATERIALS AND METHODS: The methanolic extract (E-MeOH) and buthanolic fraction (Fr-Bu) obtained from V. tucanorum were challenged by different necrotizing agents in rodents. NO-synthase inhibitor (L-NAME) and SH blocker (NEM) were used to evaluate the participation of cytoprotective factors in E-MeOH and Fr-Bu gastroprotection. Antiulcerogenic action of V. tucanorum was evaluated in rats and mice at doses 250, 500 or 1000 mg/kg (E-MeOH) and 37.5, 75 or 150 mg/kg (Fr-Bu). RESULTS: Both E-MeOH and Fr-Bu present elevated gastroprotective action in all in vivo experimental models, without signs of acute toxicity. The mechanisms involved in the gastroprotective action of E-MeOH and Fr-Bu are related to the antioxidant activity and protection to gastric mucosa NO levels. Phytochemical investigations of Fr-Bu identified different pentacyclic triterpenoids such as betulinic acid, erythrodiol, epi-betulinic acid and mixtures of ursolic acid and oleanolic acid derivatives as the major constituents. The presence of such triterpenoids in Fr-Bu is probably related to the potent gastroprotective action of this medicinal plant species. CONCLUSION: Effectiveness in gastroprotection and the absence of acute toxicity indicate this species as a promising herbal drug that is in accordance with ethnopharmacological use against gastric disorders.