Androsterone biosynthesis

HI. Hagen, A. A., and Eik-Nes, K. B., Testosterone biosynthesis in the canine in vivo following infusion of 17a-hydroxy (4t- [Pg.207]

Cholesterol, the most abundant steroid, is an important constituent of cell membranes and the starting material for biosynthesis of other steroids. This includes the sex hormones, such as progesterone, estradiol, testosterone, and androsterone, adrenocortical hormones such as aldosterone and cortisone, bile salts, and vitamin D. 

A metabohte of 17a-methyltestosterone, compound CLXXXII, has been reported to possess in the dog at doses below 1 mg/kg/day [406], more potent hypocholesterolemic activity than 17a-methyltestosterone. Compound CLXXXIII (SC-12,790) [407] has been found to possess as high oral hypocholesterolemic activity as androsterone given parenterally to rats rendered hypercholesterolemic with 6-propylthiouracil [408]. Substance CLXXXIII showed no effect on cholesterol biosynthesis from mevalonate in the liver, but enhanced cholesterol excretion in the bile of rats [409]. It is worthy of note that the 3jS-epimer of CLXXXIII was found to lack significant hypocholesterolemic activity even at doses as high as 10 mg/kg [407]. 

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