CHANGES IN BILIARY EXCRETORY MECHANISMS IN BILE DUCT-LIGATED RAT

The effects of bile duct ligation on biliary excretion of bile acids, glutathione, and lipids were studied in the rat. The bile duct of the rat was ligated for three days. The biliary bile acid excretion after bile duct cannulation was higher at first, but after 90 min became low er than that in the control rat. The bile flow in the bile duct-ligate d rat was higher after bile duct cannulation and gradually decreased t o the same level as in the control rat. Biliary glutathione excretion, which has been suggested to be a driving force for the bile acid-inde pendent canalicular bile flow, was markedly decreased in the bile duct -ligated rat. The mannitol clearance was increased and the bile ductul es showed proliferation in the bile duct-ligated rat, suggesting an in crease in the ductular bile flow. Biliary excretion of lithocholate gl ucuronide was more markedly impaired than that of taurocholate. When t aurocholate was infused at higher rates, which increases bile flow and biliary excretion of bile acid and lipids in the control rat, biliary bile acid and lipid excretion remained constant in the bile duct-liga ted rat. These findings indicate that, in the bile duct-ligated rat, t he ductular bile flow was increased and bile acid-independent canalicu lar bile flow was decreased and that, although the biliary excretion o f bile acids was not as impaired as that of organic anions, the capaci ty of bile acid and lipid excretion was markedly decreased.