Verhoeven G, Cailleau J
J Steroid Biochem. 1983 Mar;18(3):365-7. doi: 10.1016/0022-4731(83)90116-4.
Prepubertal rat testes have high 5 alpha-reductase (delta 4-3-oxosteroid 5 alpha-oxidoreductase) activity and secrete various 5 alpha-reduced androgens. We demonstrate that Na-4-methyl-4-aza-3-oxo-5 alpha-pregnane-20 (S)-carboxylate, a potent inhibitor of the prostatic 5 alpha-reductase, competitively inhibits the microsomal 5 alpha-reductase of rat testis. The apparent Ki for testosterone is 3.5 nM. At a concentration of 5 X 10(-7) M this compound efficiently inhibits the 5 alpha-reductase in cultured interstitial cells derived from prepubertal rats. Testosterone and 4-androstene-3,17-dione are the major androgens produced by these cells in the presence of inhibitor. It is concluded that 4-methyl-4-aza-steroids are a useful tool in the study of steroid secretion by prepubertal Leydig cells.
青春期前大鼠睾丸具有较高的5α-还原酶（δ4-3-氧代类固醇5α-氧化还原酶）活性，并分泌多种5α-还原雄激素。我们证明，前列腺5α-还原酶的强效抑制剂Na-4-甲基-4-氮杂-3-氧代-5α-孕烷-20（S）-羧酸盐可竞争性抑制大鼠睾丸微粒体5α-还原酶。睾酮的表观Ki为3.5 nM。在5×10-7 M的浓度下，该化合物可有效抑制青春期前大鼠来源的培养间质细胞中的5α-还原酶。在存在抑制剂的情况下，睾酮和4-雄烯-3,17-二酮是这些细胞产生的主要雄激素。得出的结论是，4-甲基-4-氮杂类固醇是研究青春期前睾丸间质细胞类固醇分泌的有用工具。
