Plasma CCK levels in patients with pancreatic insufficiency.

After stimulation with a Lundh test meal, plasma concentrations of cholecystokinin (CCK) and pancreatic polypeptide (PP) and output of pancreatic enzymes were measured in 33 patients with exocrine pancreatic insufficiency and 26 healthy subjects. Patients with impairment of pancreatic function were subdivided into those with moderate and severe insufficiency. Plasma CCK and PP were measured by radioimmunoassay. Fasting plasma CCK in patients with pancreatic insufficiency (5.8 +/- 1.1 pmol/liter) did not differ significantly from controls (4.2 +/- 0.6 pmol/liter). After endogenous stimulation with a Lundh meal, plasma CCK increased in both groups without significant differences over 2 hr. Basal and stimulated plasma levels of pancreatic polypeptide (PP) were markedly decreased only in patients with severe pancreatic insufficiency. Our results demonstrate that basal and meal-stimulated CCK levels in patients with pancreatic insufficiency do not differ from controls. Furthermore the extent of functional impairment of the exocrine pancreas did not influence basal and postprandial CCK release.