The substrate for cholesterol 7alpha-hydroxylase.

S Balasubramaniam; K A Mitropoulos; N B Myant

doi:10.1016/0005-2760(75)90180-0

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The substrate for cholesterol 7alpha-hydroxylase.

S Balasubramaniam·K A Mitropoulos·N B Myant

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Abstract

The rates of incorporation of (14C) cholesterol into cholesteryl esters and 5-cholestene-3beta,7alpha-diol (7alpha-hydroxycholesterol) by rat liver microsomes, measured under conditions in which esterification and 7alpha-hydroxylation are varied independently, indicated that cholesterol is the substrate for cholesterol 7alpha-hydroxylase. The specific activities of cholesteryl esters and 7alpha-hydroxycholeste ol in incubations of microsomes labelled with (14C)cholesterol in vitro or in vivo suggest that 7alpha-hydroxycholesterol and esterified cholesterol are not derived from the same pool of free cholesterol.

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Adenosine Triphosphate Animals Cholesterol 7-alpha-Hydroxylase Coenzyme A Esters Kinetics Microsomes, Liver NADP Oxidation-Reduction Rats Steroid Hydroxylases Structure-Activity Relationship Time Factors Journal Article

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S Balasubramaniam, K A Mitropoulos, N B Myant. 1975-07-22. The substrate for cholesterol 7alpha-hydroxylase.. https://doi.org/10.1016/0005-2760(75)90180-0

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