The concentrating function of the feline gallbladder after truncal vagotomy

Truncal vagotomy is associated with a raised incidence of cholesterol gallstone disease and increase in the size of the gallbladder and of the bile acid pool. Investigations of hepatobiliary function in man and mammals after truncal vagotomy have not established if the enlarged gallbladder is simply dilated, or if the absorptive capacity of the mucosa has changed. We studied the concentrating function of the gallbladder with a perfusion technique in anaesthetized cats three weeks and three months after intrathoracic truncal vagotomy and compared the results with a control group. The histology of the gallbladder was studied with light microscopy. Three weeks after vagotomy the gallbladder size, histologic picture and concentrating function did not differ from observations in the control cats. Three months after the vagotomy the gallbladder was slightly enlarged, sludge was found in the luminal contents, an inflammatory response was seen in the mucosa and the net rate of water absorption was increased two to three times compared with the controls. Possible mechanisms in the increased rate of net water absorption are tentatively discussed.