Role of cholecystokinin in bombesin- and meal-stimulated pancreatic polypeptide secretion in dogs

This study was undertaken to delineate the role of cholecystokinin (CCK) in bombesin- and meal-stimulated pancreatic polypeptide (PP) secretion in seven conscious dogs by studying: (1) the stimulatory effect of similar plasma levels of CCK induced by a meal and infusions of bombesin and the synthetic CCK analog cerulein on plasma PP, and (2) the inhibition of PP secretion by the CCK-receptor antagonist CR-1409 during these three stimuli. The stimulation of PP secretion during bombesin (11.0±1.6 nM/hr) and after the meal (8.9±2.0 nM/hr) were significantly (P<0.05) greater than during infusion of the CCK analog cerulein (2.7±0.4 nM/hr). CR-1409 significantly inhibited the bombesin- and meal-stimulated PP secretion to 2.0±0.4 nM/hr (81%; P<0.05) and 3.1±1.2 nM/hr (47%; P<0.05), respectively, while the cerulein-stimulated PP release was almost abolished to 0.2±0.1 nM/hr (93%; P<0.05) by the drug. These findings point to an important role for CCK in the regulation of bombesin- and meal-stimulated PP secretion.Supported by grant 13-37-43 from the Netherlands Foundation for Medical Research MEDIGON and grant Si 228/7-1 from the Deutsche Forschungsgemeinschaft.