Elevated plasma cholecystokinin concentrations in exocrine pancreatic atrophy in the rat.

Rats were fed with a copper-deficient diet combined with penicillamine to produce an atrophy of the exocrine pancreas by selective destruction of the acinar cells, which are replaced by fat cells. Plasma cholecystokinin (CCK) concentrations in animals with exocrine pancreatic atrophy were 250% higher compared to control animals (21.7 +/- 7.8 vs. 6.1 +/- 1.07 pmol/l; p less than 0.001). Plasma concentrations of gastrin were significantly decreased by 44% and of gastric inhibitory polypeptide (GIP) significantly increased by 24%, while the decrease of the plasma insulin did not reach the level of significance. In the proximal duodenum a significant decrease of the CCK concentration could be observed, whereas tissue concentrations of GIP in duodenum and jejunum and gastrin in the gastric antrum remained unaltered. These data suggest that the negative feedback control of pancreatic enzyme secretion is mediated by the release of CCK.