Effects of truncal vagotomy and antrectomy on bombesin-stimulated pancreatic secretion, release of gastrin, and pancreatic polypeptide in the anesthetized dog

Abstract

The short-term effects of truncal vagotomy and antrectomy on bombesin-stimulated pancreatic secretion and release of gastrin and pancreatic polypeptide (PP) were studied in 18 anesthetized dogs. Together with an intravenous infusion of secretin (250 ng/kg/hr) bombesin (500 ng/kg/hr) was given before and after truncal vagotomy, antrectomy, and sham operation (N = 6 dogs per group). Peak incremental pancreatic protein output in response to bombesin was about 2-3 times higher before than after the different surgical procedures (tachyphylaxis). Neither truncal vagotomy nor antrectomy significantly altered the pancreatic protein response to bombesin when compared with sham operation. Bombesin produced a mean 1-hr increase over basal of 196 pM for gastrin, which was abolished by antrectomy but not appreciably affected by truncal vagotomy and sham operation. The mean 1-hr increment (207 pM) for PP in response to bombesin was not changed by truncal vagotomy, antrectomy, and sham operation. This study shows in the anesthetized dog that exogenous bombesin stimulates release of PP as well as gastrin; that the release of gastrin by bombesin is not vagally dependent; that neither truncal vagotomy nor antrectomy alter the release of PP by bombesin; and that the action of bombesin on pancreatic protein secretion does not depend on release of gastrin or on intact vagal nerves.

Central versus peripheral effects of bombesin on the release of gastrointestinal hormones in dogs

“…The data presented here confirm earlier studies showing that IV administration of bombesin increases circulating concentrations of gastrin, PP, and CCK-33 in dogs [Miyata et al, 1980;Singer et al, 1981;Taylor et al, 1979;McDonald et al, 19831. The PP-releasing action of IV-administered bombesin depends on the vagus nerve [Guzman et al, 1981;Singer et al, 1981;Taylor et al, 19791.…”

“…The PP-releasing action of IV-administered bombesin depends on the vagus nerve [Guzman et al, 1981;Singer et al, 1981;Taylor et al, 19791. Our data show that ICV injection of bombesin elevates concentrations of serum gastrin, but that it does not affect plasma levels of PP and CCK-33.…”

Effect of vasoactive intestinal peptide, bombesin and substance P on fluid secretion by isolated rat pancreatic ducts.

“…Puoti, Melchiorri, Torsoli & Erspamer, 1985;rat: Deschodt-Lanekinan. Robberecht, De Neef, Lammens & Christophe, 1976; Linari, Linari & Lutoslawska, 1977;Iwatsuki & Petersen, 1978;Anderson & Dockray, 1988;dog: Konturek, Krol & Tasler, 1976;Singer, Niebel, Lamers, Becker, Vesper, Hartmann, Diemel & Goebell, 1981;Konturek, Tasler, Konturek, Cieszkowski, Szewczyk, Hladij & Anderson, 1989;guinea-pig: Padfield, Garner & Case, 1989; pig: Lilja, Greeley & Thompson, 1984; Knuhtsen, Holst, Jensen, Knigge & Nielsen, 1985). Bombesin is a potent stimulant of enzyme secretion in all these species; however, its effects on electrolyte secretion are variable.…”