A Comparison of Glucagon, Gastric Inhibitory Peptide, and Secretin on Gallbladder Function, Formation of Bile, and Pancreatic Secretion in the Cat

The effects of glucagon, gastric inhibitory peptide (GIP), and secretin on the concentrating mechanism and the motility in the feline gallbladder have been studied in vivo. A technique by which the gallbladder in situ was perfused by an electrolyte solution made possible a simultaneous study of the motility and of the net transport of water and electrolytes across the gallbladder wall. Secretin (0.6 microgram per kg/h) was found to abolish the net absorption of water, Na+, and HCO3- and strongly reduce the net absorption of K+ and Cl-, whereas neither glucagon (1--20 microgram per kg/h) nor GIP (1--30 microgram per kg/h) was found to significantly influence the concentrating function of the gallbladder. The motility of the gallbladder was not influenced by the peptides. The formation of bile and pancreatic secretion was not changed by glucagon or GIP, whereas secretin had a potent effect.