The present study was designed to compare the curative role of proton pump inhibitors, omeprazole, rabeprazole and lansoprazole against dexamethasone-induced ulcer model. Dexamethasone (5 mg/kg/day) was used as an ulcerogen. Dexamethasone suspended in 1% CMC in water was given orally to all rats. Omeprazole (20 mg/kg), rabeprazole (20 mg/kg), and lansoprazole (20 mg/kg) were administered by oral route 30 minutes prior to dexamethasone for ulcer protective studies, gastric secretion and mucosal studies. Effects of proton pump inhibitors were determined by the evaluation of various biochemical parameters such as estimation of myeloperoxidase, cortisol, alkaline phosphatase, malondialdehyde, endogenous anti-oxidants like superoxide dismutase, catalase and reduced glutathione. In dexamethasone induced ulcer model, omeprazole showed significant decrease in malondialdehyde, myeloperoxidase, alkaline phosphatase level and increase in superoxide dismutase, catalase and reduced glutathione level as compared to rabeprazole and lansoprazole. Omeprazole showed significant reduction in cortisol content where as rabeprazole and lansoprazole did not show significant changes as compared to control. The result indicates that omeprazole is the most effective and selective proton pump inhibitor in dexamethasone induced ulcer model as compared to rabeprazole and lansoprazole.
Keywords: Catalase; cortisol; dexamethasone; myeloperoxidase; proton pump inhibitors; superoxide dismutase.