In OCtober 1986, recognized authorities from a variety of disciplines met in Lisbon, Portugal, to review recent knowledge on eicosanoids - i. e., prostaglandins, throm boxane A, and leukotrienes - and their role in gastrointestinal diseases. 2 Briefly, in the stomach endogenous as well as exogenous prostaglandins may mediate cytoprotective actions in that they stimulate gastric mucus production, bicar bonate secretion and cellular regeneration while providing adequate mucosal blood flow. In contrast, thromboxane A2 by vasoconstriction may act as an ulcerogenic substance. Diarrheal states may...