Effect of total extrinsic denervation and atropine on HCl-stimulated pancreatic exocrine secretion and CCK release in conscious dogs.

In 10 dogs with pancreatic fistulas, we studied the effect of extrinsic pancreatic innervation and atropine on protein and bicarbonate secretion and cholecystokinin (CCK) release after intraduodenal perfusion with HCl. Before and after extrinsic denervation of the pancreas, the dogs were given 0.05 M HCl in increasing doses (1.5-48 mmol/h). Tests were repeated with atropine. Increasing doses of HCl resulted in a dose-dependent release of protein and bicarbonate output in both the intact and the denervated pancreas. However, pancreatic denervation significantly decreased pancreatic secretion in response to low loads but not to high loads of HCl. HCl-stimulated CCK release was not altered by pancreatic denervation. In the intact pancreas, atropine significantly reduced bicarbonate and protein response to low loads but not to high doses of HCl. In the denervated gland, atropine had no further inhibitory effect on exocrine pancreatic secretion. Furthermore, atropine showed no influence on HCl-stimulated CCK release under either condition.