Habib F K, Rafati G, Robinson M R, Stitch S R
J Endocrinol. 1979 Dec;83(3):369-78. doi: 10.1677/joe.0.0830369.
The in-vitro metabolism of testosterone in benign and malignant prostatic tissue was examined and distinct quantitative differences between the two types of specimens were observed. The major metabolite of testosterone in the hyperplastic prostate was 5 alpha-dihydrotestosterone and a high 3 alpha(beta)-hydroxysteroid dehydrogenase activity was also detected. In the malignant tissue, 5 alpha-reductase activity was considerably reduced and there was little or no androstanediol formed; the 17 beta-dehydrogenase activity was, however, higher than in the benign tissue. The decrease in 5 alpha-reductase was always followed by a compensatory change in the 3 alpha(beta)-hydroxysteroid dehydrogenase of the malignant prostate. The present study revealed that the ratio of the mean activities of 5 alpha-reductase to 3 alpha(beta)-hydroxysteroid dehydrogenase in the two types of specimen always remained a constant. Although the antioestrogen, tamoxifen, induced an inhibitory effect on the activities of 5 alpha-reductase and 17 beta-hydroxysteroid dehydrogenase in the gland, the present investigation also suggested that tamoxifen stimulated the activity of 3 alpha(3 beta)-hydroxysteroid dehydrogenase. In blood, the action of tamoxifen appeared to be confined to the displacement of androgens from the binding sites on the sex hormone binding globulin.
对良性和恶性前列腺组织中睾酮的体外代谢进行了检测，观察到两种标本之间存在明显的定量差异。增生性前列腺中睾酮的主要代谢产物是5α-二氢睾酮，同时还检测到较高的3α（β）-羟基类固醇脱氢酶活性。在恶性组织中，5α-还原酶活性显著降低，几乎没有或没有形成雄烷二醇；然而，17β-脱氢酶活性高于良性组织。恶性前列腺中5α-还原酶的降低总是伴随着3α（β）-羟基类固醇脱氢酶的代偿性变化。本研究表明，两种标本中5α-还原酶与3α（β）-羟基类固醇脱氢酶的平均活性比值始终保持恒定。虽然抗雌激素药物他莫昔芬对腺体中5α-还原酶和17β-羟基类固醇脱氢酶的活性有抑制作用，但本研究也表明他莫昔芬刺激了3α（3β）-羟基类固醇脱氢酶的活性。在血液中，他莫昔芬的作用似乎仅限于从性激素结合球蛋白的结合位点上置换雄激素。
