Relationship between postprandial release of CCK and PP in health and in chronic pancreatitis

The aim of this study was to investigate the relationship between postprandial release of cholecystokinin (CCK) and pancreatic polypeptide (PP) in healthy subjects and patients with chronic pancreatitis (CP). 14 patients with CP and 14 age-matched healthy subjects were studied. Diagnosis of CP was confirmed by standardized imaging modalities (ERCP and CT). Exocrine pancreatic function was assessed in all 28 subjects using the pancreolauryl serum test (PLT). An oral test meal was administered to stimulate endogenous hormone release. Plasma samples were taken before and at several time points after the test meal. CCK and PP plasma levels were measured by specific radioimmunoassays. Basal CCK and PP plasma levels were not different between patients with CP and controls, and were not correlated in either group. However, a direct linear correlation between integrated postprandial release of CCK and PP was found in healthy subjects (r = 0.74, P < 0.005). This postprandial coupling was not evident in patients with CP (r = 0.16; n.s.). Peak fluorescein serum concentration in patients with CP and steatorrhea (SCP) (n = 6) was < 2.5 micrograms/ml, and CCK and PP responses to the meal were significantly impaired (CCK response = 61 +/- 14 pmol/l/120 min in SCP vs. 110 +/- 14 in controls, P < 0.05; PP response = 3920 +/- 1773 pg/ml/120 min in SCP vs. 13418 +/- 3299 in controls, P < 0.05). In patients with mild/moderate exocrine insufficiency, CCK and PP responses varied greatly and were not different from controls.(ABSTRACT TRUNCATED AT 250 WORDS)