title: Inhibition of testosterone metabolism in the brain and cloacal gland of the quail by specific inhibitors and antihormones.
abstract: The effects of antioestrogens, antiandrogens and of various inhibitors of testosterone metabolism on testosterone metabolism in the quail hypothalamus and cloacal gland were studied by an in-vitro radioenzymatic assay. It was found that antioestrogens and antiandrogens generally had little or no effect on aromatase and 5 alpha- and 5 beta-reductases of testosterone, except when used at very high doses. The 5 alpha-reductase inhibitor, 17 beta-N,N-diethylcarbamoyl-4-methyl-4-aza-5 alpha-androstan-3-one, inhibited both 5 alpha- and 5 beta-dihydrotestosterone production without markedly affecting aromatase activity. Surprisingly, the aromatase inhibitor, 1,4,6-androstatriene-3,17-dione, inhibited not only the production of oestradiol but also that of 5 beta-dihydrotestosterone and, to a lesser extent, 5 alpha-dihydrotestosterone. These unexpected properties should be taken into account when interpreting the results of in-vivo experiments using these compounds.
mesh_terms: D000726:Androgen Antagonists / Q000494:pharmacology*; D000731:Androstanes / Q000494:pharmacology; D000733:Androstatrienes / Q000494:pharmacology; D000818:Animals; D001378:Azasteroids / Q000494:pharmacology; D002988:Cloaca / Q000187:drug effects / Q000378:metabolism*; D003370:Coturnix / Q000502:physiology*; D003534:Cyproterone / Q000031:analogs & derivatives / Q000494:pharmacology; D017373:Cyproterone Acetate; D004965:Estrogen Antagonists / Q000494:pharmacology*; D005485:Flutamide / Q000494:pharmacology; D007031:Hypothalamus / Q000187:drug effects / Q000378:metabolism*; D008297:Male; D009594:Nitromifene / Q000494:pharmacology; D011784:Quail / Q000502:physiology*; D013629:Tamoxifen / Q000494:pharmacology; D013739:Testosterone / Q000378:metabolism* / Q000494:pharmacology
chemical_list: D000726:Androgen Antagonists; D000731:Androstanes; D000733:Androstatrienes; D001378:Azasteroids; D004965:Estrogen Antagonists; D013629:Tamoxifen; C051710:L 636028; C011658:androsta-1,4,6-triene-3,17-dione; D013739:Testosterone; D017373:Cyproterone Acetate; D009594:Nitromifene; D005485:Flutamide; D003534:Cyproterone