Release of pancreatic polypeptide in humans by infusion of cholecystokinin.
Plasma levels of pancreatic polypeptide were measured after a test meal and after infusion of graded doses of 99% pure cholecystokinin in 6 healthy volunteers. Initial attempts at sterilization of 99% pure cholecystokinin resulted in complete inactivation. Successful sterilization was accomplished by filtration by using specially treated silver-coated filters. Biologic activity of sterilized material was confirmed with cholecystokinin bioassay, and plasma levels of sterilized cholecystokinin achieved by exogenous infusions were measured with a specific cholecystokinin radioimmunoassay. Significant increases in plasma levels of pancreatic polypeptide were found with a test meal and with infusions of 0.25 and 0.5 micrograms/kg-hr of 99% pure cholecystokinin. Integrated values of pancreatic polypeptide released by the low-dose and the high-dose infusions of 99% pure cholecystokinin were 59% and 50% of that obtained by food, respectively. Integrated levels of cholecystokinin after 45 min of infusion of 0.25 micrograms/kg-hr were equal to those after a standard meal. Cholecystokinin, therefore, is an effective humoral releaser of pancreatic polypeptide in humans and may play an important role in the intestinal phase of release of pancreatic polypeptide.
D000328:Adult; D002766:Cholecystokinin / Q000502:physiology*; D004435:Eating; D006801:Humans; D008297:Male; D008875:Middle Aged; D010191:Pancreatic Polypeptide / Q000097:blood / Q000378:metabolism*; D011863:Radioimmunoassay
D010191:Pancreatic Polypeptide; D002766:Cholecystokinin