title: Aromatization of androgens to estrogens mediates increased activity of glucose 6-phosphate dehydrogenase in rat levator ani muscle.
abstract: Administration of testosterone propionate to immature male rats caused a 50% increase in the specific activity of glucose 6-phosphate dehydrogenase, the rate-limiting enzyme of the pentose phosphate pathway, in the levator ani muscle. This effect appears to be mediated by conversion of testosterone to estradiol because of the following results: 1) the effect was not mimicked by the nonaromatizable androgens fluoxymesterone or 5 alpha-dihydrotestosterone; 2) it was mimicked by 17 beta-estradiol and diethylstilbestrol; 3) it was blocked by an estrogen antagonist but not by an androgen antagonist; 4) the inactive steroid 17 alpha-estradiol was without effect on glucose 6-phosphate dehydrogenase; and 5) the effect of testosterone was blocked by an inhibitor of androgen aromatase. These results demonstrate a direct effect of estrogen on striated muscle.
mesh_terms: D000728:Androgens / Q000494:pharmacology; D000735:Androstenedione / Q000031:analogs & derivatives / Q000494:pharmacology; D000737:Androstenols / Q000494:pharmacology; D000818:Animals; D047072:Aromatase Inhibitors; D004958:Estradiol / Q000096:biosynthesis* / Q000494:pharmacology; D006150:Guanine Nucleotides / Q000378:metabolism*; D006153:Guanosine Diphosphate / Q000378:metabolism*; D008297:Male; D009132:Muscles / Q000187:drug effects / Q000201:enzymology*; D051381:Rats; D013739:Testosterone / Q000378:metabolism* / Q000494:pharmacology
chemical_list: D000728:Androgens; D000737:Androstenols; D047072:Aromatase Inhibitors; D006150:Guanine Nucleotides; D006153:Guanosine Diphosphate; D013739:Testosterone; D000735:Androstenedione; D004958:Estradiol