The effect of bile duct ligation on hepatic bile acid sulfotransferase activity in the hamster

Bile duct ligation has been studied in adult hamsters to examine its effect on the capacity of the liver to carry out enzymatic sulfation of glycochenodeoxycholic acid. The increased urinary excretion of bile acid sulfate esters which occurs following bile duct ligation in hamsters may be a result of such enhanced capacity. However, in vitro enzyme activity was reduced by bile duct ligation compared to control animals at each concentration of substrate tested, the reduction being greater for females than males. This was due to a fourfold increase in apparent K m in female animals to values similar to those observed in control male animals, and may occur because of loss of sensitivity to estrogen. The reduced hepatic enzyme activity was partly compensated by a small increase in liver mass in males, but not females. Increased urinary excretion of bile acid sulfates in bile duct-ligated hamsters is consistent with greater substrate availability and impeded biliary excretion of the sulfate metabolites.