Profile of gastrointestinal damage induced by platelet-activating factor.

The ulcerogenic actions of an intravenous infusion of platelet-activating factor (100 ng/kg/min) was studied in the rat. Damage to the stomach, duodenum, jejunum, ileum and colon were assessed histologically and using intraluminal acid phosphatase release as a marker of cellular damage. A 10-min infusion of platelet-activating factor caused extensive haemorrhagic damage to each of the regions examined, with the exception of the colon. Acid phosphatase release was significantly elevated in the stomach, jejunum, ileum (p less than 0.001) and duodenum (p less than 0.01), but not in the colon. These studies demonstrate that platelet-activating factor is a potent ulcerogen in the stomach and small intestine, and support a role for this endogenous phospholipid as a mediator of the ulceration associated with endotoxin-induced shock.