Effect of secretin and jejunal acidification on gastric and pancreatic secretion in man

The inhibitory effect of intravenous secretin and intrajejunal acid infusion on basal and pentagastrin-induced gastric acid secretion as well as the stimulatory influence of both infusions on pancreatic flow rate and bicarbonate output were compared in two groups of healthy subjects.

Secretin strongly inhibited basal acid output and slightly decreased pentagastrin induced gastric secretion.

Intrajejunal acid infusion did not affect the gastric secretion but resulted in an increase in pancreatic volume flow and bicarbonate output reaching about 40% of the pancreatic response to secretin¹ infused intravenously in a dose of 2 units per kilogram per hour.

It is concluded that this provides evidence that secretin is a strong inhibitor of spontaneous gastric acid secretion and that acid in the jejunum causes the release of secretin in man.