文章基本信息

标题：Regulatory effects of dietary sterols and bile acids on rat intestinal HMG CoA reductase
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作者：S. Shefer ; S. Hauser ; V. Lapar 等
期刊名称：JLR Papers In Press
印刷版ISSN：0022-2275
电子版ISSN：1539-7262
出版年度：1973
卷号：14
期号：4
页码：400-405
语种：English
出版社：American Society for Biochemistry and Molecular Biology
摘要：The specific activity (concentration) of microsomal HMG CoA reductase of intestinal crypt cells was studied in rats fed sterols and bile acids, either singly or in combination. It was found that the basal activity of the reductase was not suppressed by the administration of relatively large amounts of bile acid (taurocholate or taurochenodeoxycholate). Bile acids reduced the specific activity of the reductase only in rats in which the activity of the enzyme had first been enhanced by biliary diversion or by sitosterol feeding. In addition, bile acid feeding abolished the diurnal elevation of reductase activity that normally occurs between midnight and 2 a.m. In no case did bile acids reduce enzyme activity below basal levels. A pronounced (60%) reduction of intestinal HMG CoA reductase activity was observed in rats fed cholesterol and bile acid in combination. This reduction in activity could not be ascribed to an increase in intestinal bile acid flux but was associated with an increase in sterol concentration within the intestinal crypt cells. These results indicate that dietary sterols and bile acids both play a role in the regulation of intestinal HMG CoA reductase.
关键词：intestinal absorption ; microsomal enzyme ; intestinal crypt cells ; taurocholate ; taurochenodeoxycholate ; sitosterol ; rate-determining step ; cholesterol biosynthesis ; ileum ; jejunum