title: Androgen receptor binding and antiandrogenic activity of some 4,5-secoandrostanes and ring B cyclopropanoandrostanes.
abstract: Eight androstane derivatives with modified ring A or B (4,5-secoandrostanes and ring B cyclopropanoandrostanes) were assayed in vivo on mice for their antiandrogenic activity and the effect was compared with that of cyproterone acetate. The inhibition of dihydrotestosterone binding to rat prostate cytosol and to human plasmatic sex hormone binding protein was correlated with the in vivo effect. The antiandrogenic activity of 6 alpha,7 alpha-cyclopropano-5 alpha-androstane-3 beta,17 beta-diol was nearly as high as that of cyproterone acetate. The opening of ring A of androgens, such as testosterone or 17 alpha-methyltestosterone, moderately reduced the binding and changed the biological activity to weakly antiandrogenic.
mesh_terms: D000726:Androgen Antagonists / Q000494:pharmacology*; D000731:Androstanes / Q000494:pharmacology*; D000818:Animals; D001681:Biological Assay; D003534:Cyproterone / Q000031:analogs & derivatives / Q000494:pharmacology; D017373:Cyproterone Acetate; D013196:Dihydrotestosterone / Q000378:metabolism; D005260:Female; D006801:Humans; D008297:Male; D009929:Organ Size / Q000187:drug effects; D011247:Pregnancy; D011467:Prostate / Q000378:metabolism; D051381:Rats; D011919:Rats, Inbred Strains; D011944:Receptors, Androgen / Q000378:metabolism*; D011987:Receptors, Steroid / Q000378:metabolism*; D012632:Secosteroids / Q000494:pharmacology*; D012669:Seminal Vesicles / Q000187:drug effects; D013329:Structure-Activity Relationship; D013739:Testosterone / Q000494:pharmacology
chemical_list: D000726:Androgen Antagonists; D000731:Androstanes; D011944:Receptors, Androgen; D011987:Receptors, Steroid; D012632:Secosteroids; D013196:Dihydrotestosterone; D013739:Testosterone; D017373:Cyproterone Acetate; D003534:Cyproterone