Release of Cholecystokinin in Conscious Dogs; Correlation With Simultaneous Measurements of Gallbladder Pressure and Pancreatic Protein Secretion

We have used an antibody that cross-reacts with cholecystokinin-33139 to measure cholecystokinin release into plasma; this release was correlated with simultaneous measurements of gallbladder pressure and pancreatic protein secretion in response to intestinal administration of fat. Nine conscious dogs were prepared with chronic gastric, pancreatic, and gallbladder fistulas. Plasma cholecystokinin, gallbladder pressure, and pancreatic protein output were measured simultaneously before, and at intervals during, a 2-h intraduodenal infusion of sodium oleate. This infusion resulted in significant (p < 0.05) elevations of plasma cholecystokinin (from 64 ± 7 to 181 ± 27 pg/ml), in gallbladder pressure (from 13 ± 1 to 27 ± 3 cmH₂O), and in pancreatic protein output (from 65 ± 7 to 148 ± 21 mg/15 min); all measurements are from the basal state to 120 min after the onset of duodenal perfusion. Plasma concentrations of cholecystokinin were significantly correlated with gallbladder pressure (r = 0.91, p < 0.05) and pancreatic protein output (r = 0.84, p < 0.05). These data provide evidence that release of endogenous cholecystokinin, as measured by radioimmunoassay, can be correlated with the classic biologic actions ascribed to cholecystokinin.