Platelet-activating factor may mediate dexamethasone-induced gastric damage in the rat.

The possible role of platelet-activating factor (PAF) in dexamethasone-induced gastric mucosal damage was studied in rats. PAF was measured by a platelet aggregation assay. The identity of the PAF-like product recovered from gastric tissues was ascertained by thin-layer chromatography and high-pressure liquid chromatography. Low levels of PAF were detected in the normal rat stomach, while in dexamethasone-treated animals PAF levels were significantly higher. Pretreatment of the animals with BN 52021, a specific PAF receptor antagonist, significantly attenuated dexamethasone-induced mucosal injury. These findings suggest that PAF may be a mediator of mucosal damage induced by glucocorticoids.