The effects E and A prostaglandins on gastric mucosal blood flow and acid secretion in the rat.

1. The effects of prostaglandins E(1), E(2), A(1) and A(2) on gastric acid secretion and mucosal blood flow were studied by means of a [(14)C]-aniline clearance technique in the anaesthetized rat.2. During intravenous administration of these prostaglandins, in doses which almost completely inhibited pentagastrin- and histamine-induced acid secretion, a fall in clearance was observed.3. Clearance per unit acid secretion increased during prostaglandin administration, precluding a primary reduction in mucosal blood flow as the mechanism of the antisecretory action.4. Prostaglandins increased clearance during basal secretion, indicating a direct vasodilator effect on the gastric mucosa.5. The possibility that endogenous prostaglandins contribute to functional vasodilatation in the gastric mucosa and that exogenous prostaglandins may be of clinical value in the treatment of peptic ulcer is discussed.