Dept. of Biochemistry (생화학); Institute for Medical Science (의과학연구소)
Keimyung Medical Journal, Vol.20(1) : 1, 2001
The possible mechanisms of
increased glyoxalase I (GLO-I) activity in cholestatic rat liver and serum were studied. These hepatic and serum enzyme activities were determined from the experimental rats with choledocho-caval shunt (CCS) or bile duct obstruction (BDO). The Michaelis-Menten constants in this hepatic enzyme were also measured. The activities of hepatic and serum GLO-I as well as the Vmax value of this hepatic enzyme were found to be increased significantly in both CCS plus taurocholic acid (TCA) injected group and BDO plus TCA injected group than in each control group such as CCS alone and BDO alone. In addition, these serum and hepatic enzyme activities did not change in both the CCS plus tauroursodeoxycholic acid injected group and the BDO plus tauroursodeoxycholic acid injected group. On the other hand, the value of Km of the above hepatic enzyme did not change in any experimental group. Above results suggest that TCA induce the biosynthesis of GLO-I in the liver. The elevated activity of the serum GLO-I is believed to be caused by the increment of membrane permeability of hepatocytes upon TCA mediated liver cell necrosis.