MUCOSAL PROTECTIVE EFFECT OF LEMINOPRAZOLE ON REFLUX ESOPHAGITIS INDUCED IN RATS

We examined the effect of leminoprazole (an acid pump inhibitor) on re flux esophagitis induced in rats. Intragastrically administered lemino prazole significantly and dose-dependently protected the esophageal mu cosa against the reflux of gastric contents, without affecting gastric acid secretion. However, it had no effect on the esophagitis when adm inistered intraduodenally, despite its significant inhibition (about 4 0%) of gastric acid secretion. Omeprazole significantly prevented the development of esophagitis, most probably through potent inhibition of gastric acid secretion. Indomethacin significantly reduced the synthe sis of prostaglandin E(2) in the esophagus. Since indomethacin pretrea tment had no effect on the esophageal protection by leminoprazole, ome prazole or sucralfate, the involvement of endogenous prostaglandins ca n be ruled out as a possible underlying mechanism. Intragastrically, b ut not intraduodenally, administered sucralfate significantly prevente d the esophagitis even at a dose not affecting gastric acid secretion. These results strongly suggest that both leminoprazole and sucralfate protect the esophageal mucosa directly.