Role of endogenous CCK in regulation of interdigestive pancreatic exocrine secretion in sheep (Ovis aries)

Abstract

The role of endogenous cholecystokinin (CCK) in the regulation of pancreatic exocrine secretion during the interdigestive period was studied in conscious sheep. Intravenous infusion of proglumide (15, 30 and 60 mumol/kg/min) for 70 min significantly decreased flow rate, protein and amylase output in pancreatic juice by 80% at the maximum dose, as well as atropine (10 micrograms/kg/min), without a significant decrease in plasma concentration of immunoreactive CCK. Intravenous injection of CCK (114 pmol/kg) increased the pancreatic secretion during atropine infusion, but not during proglumide infusion. These results suggest that the regulation of interdigestive pancreatic exocrine secretion in sheep depends greatly on endogenous CCK as well as on the cholinergic mechanism.