Gastroprotective activity of α-terpineol in two experimental models of gastric ulcer in rats

BACKGROUND AND THE PURPOSE OF THE STUDY Several plant essential oils, as well as terpenes present in essential oils, have shown gastroprotective activity. The aim of the present work was to evaluate the gastroprotective activity of α-terpineol, a monoterpene alcohol which is present in essential oils of various plants. METHODS The gastroprotective activity of α-terpineol was evaluated in rats by assessing the changes in ethanol and indomethacin-induced gastric ulcer scores and on gastric secretory volume and total acidity in pylorus-ligated rats. Alpha-terpineol was administrated orally at the doses of 10, 30, and 50 mg/kg one hour before administration of the ulcer inducing agents by the pylorus ligation procedure. The involvement of endogenous prostaglandins in the protective effect of α-terpineol in ethanol-induced gastric lesions test was assessed by administration of indomethacin (10 mg/kg, s.c.) 30 min before oral administration of α-terpineol at the dose of 50 mg/kg. RESULTS α-terpineol presented gastroprotective activity against ethanol-induced ulcers at the doses of 10, 30, and 50 mg/kg. Epoxy-carvone at the dose of 10 mg/kg did not present gastroprotective activity against ulcer induced by indomethacin, but at the doses of 30 and 50 mg/kg it attenuated the gastric damages induced by this agent significantly. Pretreatment with indomethacin did not prevent the gastroprotective effect of α-terpineol on ethanol-induced ulcers. Alpha-terpineol also did not affect the gastric secretion in pylorus-ligated rats. MAJOR CONCLUSION The results suggest that α-terpineol presents gastroprotective action which does not involve either an increase in the synthesis of endogenous prostaglandin or a decrease in the gastric acid secretion.