title: Inhibition of testosterone 5 alpha-reductase by and antiandrogenicity of allenic 3-keto-5,10-secosteroids.
abstract: (4R)-5,10-seco-19-norpregna-4,5-diene-3,10,20-trione(II), A 3-keto-5,10-secosteroid which is an irreversible inhibitor of delta 5-3-ketosteroid isomerase was tested for its possible antiandrogenicity in the hamster flank organ test. The organs of female animals topically treated with 4 microgram of testosterone propionate (TP) for 4 weeks enlarged in size and showed pigmentation resembling adult males. When compound II was applied concomitantly with TP, androgenic stimulation was completely blocked and the flank organs remained small like those of female animals. These results suggest that compound II may be a useful anti-androgen when applied topically. It may well act mainly by inhibition of the formation of 5alphs-reduced metabolites was markedly inhibited.
mesh_terms: D058891:5-alpha Reductase Inhibitors; D015113:Androstane-3,17-diol / Q000378:metabolism; D000818:Animals; D006224:Cricetinae; D013196:Dihydrotestosterone / Q000378:metabolism; D005260:Female; D008297:Male; D009649:Norpregnadienes / Q000494:pharmacology*; D010088:Oxidoreductases / Q000037:antagonists & inhibitors*; D010858:Pigmentation / Q000187:drug effects; D011467:Prostate / Q000201:enzymology; D013739:Testosterone / Q000378:metabolism / Q000494:pharmacology
chemical_list: D058891:5-alpha Reductase Inhibitors; D009649:Norpregnadienes; D013196:Dihydrotestosterone; D015113:Androstane-3,17-diol; D013739:Testosterone; D010088:Oxidoreductases