Conversion of testosterone and androstenedione to 5 beta-androstanes by adult male hamster liver cytosol.
The incubation of [4-14C]testosterone with adult male hamster liver cytosol at pH 6.7 yielded 5 beta-androstane-3 alpha, 17 beta-diol and small quantities of 5 beta-androstane-3 beta, 17 beta-diol, 17 beta-hydroxy-5 beta-androstan-3-one, 3 alpha-hydroxy-5 beta-androstan-17-one and androstenedione. The use of [4-14C]androstenedione as substrate yielded the same 5 beta-metabolites and also testosterone and a trace of epitestosterone. 5 beta-Androstane-3 alpha, 17 beta-diol was the major metabolite at "low" concentrations of substrate but testosterone and 3 alpha-hydroxy-5 beta-androstan-17-one became the major metabolites as the concentration of the substrate was increased. Small quantities of 5 beta-androstane-3,17-dione and 3 beta-hydroxy-5 beta-androstan-17-one were detected at "high" while 5 beta-androstane-3 alpha, 17 alpha-diol was detected at "low" concentrations of androstenedione. NADPH was more effective than NADH except in the formation of the 3 beta-steroids. Furthermore, the 3 beta-steroids were formed in maximum quantities at a lower pH than the other metabolites. The relative production of the metabolites was consistent with their respective spectrophotometrically determined degree of hydroxyl dehydrogenation.
D000731:Androstanes / Q000096:biosynthesis*; D000735:Androstenedione / Q000378:metabolism*; D000818:Animals; D006224:Cricetinae; D003600:Cytosol / Q000378:metabolism; D005260:Female; D006863:Hydrogen-Ion Concentration; D066298:In Vitro Techniques; D008099:Liver / Q000201:enzymology / Q000378:metabolism*; D008297:Male; D010084:Oxidation-Reduction; D010088:Oxidoreductases / Q000378:metabolism*; D013739:Testosterone / Q000378:metabolism*
D000731:Androstanes; D013739:Testosterone; D000735:Androstenedione; D010088:Oxidoreductases