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Nonisotopic Method for Estimating Cholesterogenesis in the Rat

  • W. A. Phillips
  • J. M. Ratchford
  • J. R. Schultz
Part of the Advances in Experimental Medicine and Biology book series (AEMB, volume 67)

Abstract

Influence of several compounds on sterol production was determined from serum desmosterol (D) levels in rats treated with U-18666A:3β-(2-diethylaminoethoxy)androst-5-en-17-one HCl. U-18666A blocks biosynthesis of cholesterol (C) by inhibiting conversion from D to C. Diets containing C (2%), the bile acid sequestrant colestipol HCl (1%), clofibrate (0.2%), combination of colestipol HCl and clofibrate, or basal diet were fed to normal or U-18666A (3 mg/kg/d) male rats for 2 weeks. In normal rats, C feeding increased serum C levels (39%), colestipol HCl had no significant effect, while clofibrate or the combination with colestipol HCl reduced C levels to the same extent (37%). In U-18666A-treated rats, C feeding reduced D concentration (30 to 13 mg/dl) indicating inhibition of synthesis via negative feedback system. Colestipol HCl increased D level (33%) and reduced C (60%) indicating increased synthesis; results are compatible with an agent capable of binding bile acids in the rat which can compensate for loss of these acids by increasing sterol synthesis. Compared to control, clofibrate reduced serum C (33%) and D (43%); in combination with colestipol HCl it inhibited the increased synthesis caused by the latter. Clofibrate appears to be an inhibitor of C biosynthesis. Also, tests with other compounds make it apparent that the U-18666A-treated rat model system can be useful in evaluating cholesterogenesis.

Keywords

Bile Acid Serum Cholesterol Basal Diet Normal Animal Cholesterol Biosynthesis 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.

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Copyright information

© Springer Science+Business Media New York 1976

Authors and Affiliations

  • W. A. Phillips
    • 1
  • J. M. Ratchford
    • 1
  • J. R. Schultz
    • 1
  1. 1.Diabetes and Atherosclerosis ResearchThe Upjohn CompanyKalamazooUSA

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