Effects of sucralfate or mild irritants on experimental gastritis and prostaglandin production.

Rats pretreated with dilute ethanol, dilute hydrochloric acid, or dilute sodium hydroxide had significantly less gastric mucosal damage when they were exposed 15 or 30 minutes later to strong irritants. The dilute agents, known as mild irritants, also caused an increase in the production of gastric mucosal prostaglandin E2 at the 15- and 30-minute dosing intervals. This suggests that the mild irritants are only effective in providing gastric mucosal protection when they increase gastric production of prostaglandin E2. Sucralfate treatment also caused an increase in gastric mucosal production of prostaglandin E2 at only the 15- and 30-minute dosing intervals. In contrast, pretreatment with sucralfate protected against the damaging effects of the strong irritants for at least 480 minutes. Therefore, prostaglandin E2 may play a role in sucralfate's protective effect at short dosing intervals, but at longer intervals, when prostaglandin E2 changes were not observed, sucralfate was still found to be very effective in reducing the severity of gastritis. This suggests that sucralfate acts, at least in part, through some other mechanism(s) besides increasing gastric mucosal prostaglandin E2 production.