Induction of 
Cholestatic Rat Liver 5'-Nucleotidase by Taurocholic Acid Load

Keimyung Medical Journal 2001;20(2):129-139.

Induction of Cholestatic Rat Liver 5'-Nucleotidase by Taurocholic Acid Load

Taurocholic Acid 부하에 의한 쥐 담즙울체간에서 5'-nucleotidase의 유도

김성국; 김여희; 곽춘식

Abstract

Possible mechanisms of increase of 5' -nucleotidase (5'-NT) activity in cholestatic rat liver and serum were studied. The hepatic subcellular and serum 5'-NT activities in experimental rats with choledocho-caval shunt (CCS) or bile duct obstruction (BDO) were determined. The Michaelis-Menten constants of these hepatic enzymes were measured. The activities of serum and hepatic cytosolic and microsomal 5'-NT as well as Vmax values of 5" -NT were found to be significantly increased in both CCS plus taurocholic acid (TCA) injected group and BDO plus TCA injected group; compared with the CCS and BDO groups;respectively. However; Km values of the above hepatic 5' -NT did not change in any experimental group. The above results suggest that TCA stimulates biosynthesis of 5'- NT in the liver and the elevated 5' -NT activity in the serum is most likely due to an increase in membrane permeability of hepatocytes upon TCA mediated liver cell necrosis.

Key Words: Bile duct obstruction, Choledocho-caval shunt, 5'-nucleotidase, Taurocholic acid, Tauroursodeoxycholic acid