Potentiation effect of secretin on cholecystokinin-stimulated pancreatic secretion in dogs

G252, 1984.-A possible potentiating effect of cholecystokinin octapeptide (CCK-OP) on the action of secretin on exocrine pancreatic secretion was studied in five dogs with gastric fs-tulas and modified Herrera pancreatic fistulas. Secretin in a dose, 2.45 pmol (0.03 clinical units) l kg-‘. h-l, that mimics the plasma secretin level in the postprandial state increased pan-creatic bicarbonate secretion, but the increase was not statIs-tically significant. CCK-OP in graded doses, 26.2, 52.5, 169, and 219 pmol (0.03, 0.06, 0.125, and 0.25 pg). kg?‘. h?, given intravenously produced a significant increase in both b&carbon-ate and protein secretion, and the increase was dose related. The plasma concentrations of immunoreactive CCK during intravenous infusion of CCK-OP in doses of 26.2 and 52.5 pmol. kg-l. h-l were found to mimic the postprandial plasma concentrations of immunoreactive CCK in eight dogs. Whe