Influence of sex and sex hormones on the oxidation of cholesterol-26-C14 by rat liver mitochondria*†

• Main Authors: David Kritchevsky, Shirley A. Tepper, Ezra Staple, Michael W. Whitehouse
• Format: Article
• Language: English
• Published: Elsevier 1963-04-01
• Series: Journal of Lipid Research
• Online Access: http://www.sciencedirect.com/science/article/pii/S0022227520403451

The oxidation of cholesterol-26-C14, sodium propionate-1, -2, or -3-C14, and sodium octanoate-1-C14 by liver mitochondrial preparations from intact and gonadectomized rats of both sexes, and from intact and gonadectomized rats of both sexes treated with androgens and estrogens, has been studied. Mitochondria from intact female rats and mice consistently oxidized added cholesterol to a greater extent than mitochondria from intact males. There were no significant sex differences in the oxidation of sodium propionate (a possible intermediate in the oxidation of the cholesterol side chain to carbon dioxide). Surgical or chemical castration of male rats enhanced cholesterol oxidation. Androgen treatment of female rats slightly depressed cholesterol oxidation but ovariectomy had no effect. Cholesterol oxidation by preparations of normal male or female rat liver mitochondria was inhibited by sex hormones added in vitro. These sex differences in cholesterol oxidation suggest that circulating androgen, rather than estrogen, levels determine the efficiency of cholesterol oxidation. Octanoate oxidation by liver mitochondria was not influenced by prior castration or treatment of male rats with androgens or estrogens. Androgen treatment of female rats slightly inhibited octanoate oxidation while estrogen treatment enhanced octanoate oxidation.