Abstract
Mechanisms of hepatic bile secretion were studied in unanesthetized bile fistula rats. After implantation of bile fistula, bile flow and bile acids secretion were significantly decreased and secondary bile acids were greatly decreased. After cholic acid (CA) 30μM/100 g/hr infusion, bile juice was greatly increased, and CA was dramatically increased in bile. Biliary bile flow and bile acid were not increased after infusion of CDCA 30 μM/100 g/hr. CDCA was slightly increased in bile, but the amount of bile acids tended to decrease. DHCA dramatically increased the amount of bile juice, while DHCA was not detected in the bile. After DHCA infusion, 3α, 7α-dihydroxy-12-keto-5β-cholanic acid dramatically increased and slightly increased in CA. Regarding the relationship between the bile flow rate and the secretion rate of the total bile acids, bile acid-dependent bile secretion varied with the bile acid value. On the other hand, Na+ and K+ concentrations of bile were not related to bile acid concentration. These studies show that canalicular bile secretion mechanisms varied with the compositions of bile acids and bile acid secretion rate.
