Pancreatic exocrine secretion. Release of gastrin and cholecystokinin in response to bombesin in pigs.

The objective of this study was to determine whether bombesin can stimulate pancreatic exocrine secretion and release of cholecystokinin-33 and gastrin in pigs. Bombesin (1 microgram/kg-hr) was infused intravenously in six conscious piglets for one hour, and pancreatic secretions, plasma, and serum were collected. Cholecystokinin-33 and gastrin were measured by specific radioimmunoassays. Pancreatic secretory volume increased from a basal value of 1.5 +/- 0.5 mL/15 min to 10.4 +/- 1.7 mL/15 min. Pancreatic protein output increased from basal values of 7.9 +/- 2.4 mg/15 min to 88.9 +/- 25.4 mg/15 min. Plasma cholecystokinin-33 increased significantly from a basal concentration of 130 +/- 40 pg/mL to 275 +/- 100 pg/mL, as did gastrin (40.7 pg/mL to 200 +/- 27 pg/mL). Our findings demonstrated that bombesin stimulates exocrine pancreatic secretion in pigs; we conclude that this stimulation is due largely to the release of cholecystokinin.