Oda H, Kuroki S, Yamashita H, Nakayama F
Department of Surgery I, Kyushu University Faculty of Medicine, Fukuoka, Japan.
Lipids. 1990 Nov;25(11):706-10. doi: 10.1007/BF02544038.
In order to investigate the effects of bile acid feeding on hepatic microsomal deoxycholate 7 alpha-hydroxylase activity, three different bile acids were administered (0.2% w/w in chow) to hamsters for two weeks. Deoxycholate 7 alpha-hydroxylase activity was increased markedly by feeding of cholic acid (CA) and slightly by deoxycholic acid (DCA). Chenodeoxycholic acid (CDCA) had little effect on the enzyme activity. Feeding each of the bile acids significantly inhibited the activity of cholesterol 7 alpha-hydroxylase in the order CDCA greater than or equal to DCA greater than CA. There was no correlation between deoxycholate 7 alpha-hydroxylase activity and cholesterol 7 alpha-hydroxylase activity. It is concluded that the activity of deoxycholate 7 alpha-hydroxylase is up-regulated by feeding DCA and CA and that the mechanism seems to be different from that of cholesterol 7 alpha-hydroxylase. The increased activity of hepatic deoxycholate 7 alpha-hydroxylase by CA and DCA should be beneficial in minimizing the toxic effects of DCA in the hamster.
为了研究胆汁酸喂养对肝微粒体脱氧胆酸7α-羟化酶活性的影响，给仓鼠喂食三种不同的胆汁酸（饲料中含量为0.2% w/w），持续两周。喂食胆酸（CA）可使脱氧胆酸7α-羟化酶活性显著增加，而脱氧胆酸（DCA）可使其略有增加。鹅去氧胆酸（CDCA）对该酶活性影响很小。喂食每种胆汁酸均能显著抑制胆固醇7α-羟化酶的活性，抑制程度依次为CDCA≥DCA＞CA。脱氧胆酸7α-羟化酶活性与胆固醇7α-羟化酶活性之间无相关性。得出结论，喂食DCA和CA可上调脱氧胆酸7α-羟化酶的活性，且其机制似乎与胆固醇7α-羟化酶不同。CA和DCA使肝脱氧胆酸7α-羟化酶活性增加，这应有助于将仓鼠体内DCA的毒性作用降至最低。
