Secretion of labelled proteins by the isolated dog pancreas in the response to secretin and cholecystokinin.

We compared the effects of secretin (10 clinical units/hur.) and cholecystokinin-pancreiozymin (CCK-PZ 10 Ivy units/hr.) from G.I.H. Laboratory in Stockholm, Sweden, on the secretion of radioactively labelled proteins in the pancreatic juice. This was carried out on isolated dog pancreas perfused "ex-vivo" with whole heparinized oxygenated blood. CCK-PZ and secretin were infused together and the results compared with a second series of experiments where secretin alone was administered, at the same dose. Both hormones caused a discharge of labelled proteins, which was linear over 55 minutes. Secretin increased the flow rate of the pancreatic juice and to a lesser extent the enzymatic protein output. CCK-PZ stimulated the mass flow of secretory proteins.