Gastroprotective effect of the mixture of α- and β-amyrin from Protium heptaphyllum: Role of capsaicin-sensitive afferent neurons - Oliveira,F.A.; Vieira-Júnior,G.M.; Chaves,M.H.; Almeida,F.RC.; Santos,K.A.; Martins,F.S. (Planta Med, 2004)