Dissociation between acid secretion and mucosal blood flow after treatment of rats with reserpine.

The correlation between acid secretion and mucosal blood flow in the gastric mucosa after administration of reserpine to rats was determined in an attempt to define the etiology of reserpine-induced gastric erosions. Although gastric acid output was increased gradually by administration of reserpine, mucosal blood flow was not significantly affected. The increase in acid output induced by reserpine was completely prevented by pretreatment with atropine. Reserpine-induced increase in acid secretion may have been mediated by the vagus nerves, probably as a result of central and/or peripheral diminution in noradrenergic inhibitory mechanisms. The dissociation between mucosal blood flow and acid secretion, resulting in a relative ischemic state in the gastric mucosa, may have occurred in part from reduced cardiac function after treatment with reserpine. Vagal stimulation induced a parallel increase in both acid secretion and mucosal blood flow in control rats. 6-Hydroxydopamine-induced sympathectomy did not increase mucosal blood flow to a degree corresponding to the increase in acid output by vagal stimulation. In animals treated with 6-hydroxydopamine, gastric erosions occurred. We conclude that reserpine increases acid output but without a parallel increase in the mucosal blood flow and that the erosions which occur are probably due to the relative ischemic state of the gastric mucosa.