Canine gallbladder bile. Effects of proximal gastric vagotomy, truncal vagotomy, and truncal vagotomy with pyloroplasty on volume and composition.

Three groups of four dogs each underwent proximal gastric vagotomy, truncal vagotomy, or truncal vagotomy with pyloroplasty. Two dogs had sham operations. Gallbladder bile was aspirated and measured. Aliquots were cultured and assayed for cholesterol, phospholipid, and bile salts initially and at subsequent laparotomies. Both truncal vagotomy groups showed marked increases in aspirate volume at subsequent laparotomies. The sham and proximal gastric vagotomy groups showed a small initial decrease in mean aspirate volume without further significant changes. When the bile assay data were plotted on triangular coordinates, all point for all groups remained well within the area of cholesterol solubility. Nevertheless, two dogs in each truncal vagotomy group were found to have gallstones. No stones were found in the sham and proximal gastric vagotomy groups. Proximal gastric vagotomy appears to preserve fasting gallbladder bile volume and does not alter bile composition in the dog.