Role of mucus and prostaglandins in the gastric mucosal protective actions of sucralfate against ethanol-induced injury in the rat.

This study investigated the relationship between the protective effect of sucralfate against ethanol-induced gastric mucosal injury in the rat and the effects of sucralfate on prostaglandin and mucus synthesis and secretion. Sucralfate at 200, 400, and 800 mg/kg significantly reduced gastric ulceration. Intragastric administration of sucralfate increased luminal mucus and prostaglandin E2 levels but did not affect prostaglandin or mucus synthesis in gastric mucosal biopsy specimens from sucralfate-treated animals. Pretreatment with indomethacin partially reduced the protective effect of sucralfate. However, sucralfate 200 mg/kg, a dose that completely prevented ulceration, did not increase the levels of luminal prostaglandin E2. In vitro incubation with sucralfate did not stimulate mucosal prostaglandin synthesis. Longer-term administration of sucralfate for 48 or 96 hours did not stimulate mucus or prostaglandin synthesis but did increase luminal prostaglandin E2 and mucus. Although sucralfate increased the gastric juice content of prostaglandin E2 and mucus, the two did not appear to be mechanistically related, and only mucus release was consistently associated with mucosal protection.