담즙산 부하에 의한 쥐 간의 Benzoyltransferase의 유도

Abstract

To elucidate the possible mechanism of the increased activity of benzoyltrans­ferase (BT) in cholestatic liver, rats were divided into eight groups: Normal, sham operated control, bile duct obstruction (BDO) alone (BDO group), BDO plus taurocholic acid (TCA) injection (BDO plus TCA group), BDO plus tauroursodeoxycholic acid (TUDCA) injection (BDO plus TUDCA group), choledocho-caval shunt (CCS) operation (CCS group), CCS plus TCA injection (CCS plus TCA group), and CCS plus TUDCA injection (CCS plus TUDCA group). BT activity was deter­mined in the liver cytosolic, mitochondrial and microsomal preparations isolated from the above experimental rats. The values of Km and Vmax in this hepatic enzyme were measured. The activity of liver microsomal BT showed a significant increase in the CCS group. The activities of liver mito­chondrial and microsomal BT showed a significant increase in the BDO group. However, mitochon­drial and microsomal BT activities in the liver rose more rapidly in the BDO group than that of the CCS group. Mitochondrial and microsomal BT activities in the liver and its Vmax value were increased more significantly in both the CCS plus TCA group, and the BDO plus TCA group than that of each control group, such as CCS and BDO group. On the other hand, the value of Km of the hepatic subcellular BT did not changed in all the experimental groups. However, this hepatic enzyme activity did not changed in both the CCS plus TUDCA group and the BDO plus TUDCA group. Above results suggest that TCA induces the biosynthesis of BT in the liver.