Bird C E, Masters V, Sterns E E, Clark A F
Clin Invest Med. 1985;8(2):97-102.
Testosterone is a known estrogen precursor especially in postmenopausal women. Tamoxifen, an anti-estrogen, is used in the treatment of women with breast cancer in whom metastatic disease has been demonstrated. The action of Tamoxifen is thought to be to occupy the intracellular estrogen receptor sites in target tissues and thus block the action of the biologically active estrogen, estradiol. Effects of Tamoxifen on the production and metabolism of hormones have been postulated. We studied the kinetics of testosterone metabolism by the constant infusion of 3H-testosterone in six postmenopausal women with breast cancer prior to and during Tamoxifen therapy. The Tamoxifen did not produce any significant change in the metabolic clearance rate, the plasma concentration or the calculated blood production rate of testosterone. The only significant alteration in the conversion ratio of testosterone to metabolites was the reduction (p less than 0.02) in conversion to 5 alpha-dihydrotestosterone. A significant reduction in the plasma concentrations (p less than 0.05) of dehydroepiandrosterone and of luteinizing hormone (p less than 0.02) was found. Other steroid and peptide hormones did not show any significant changes. We conclude that Tamoxifen therapy has very little effect on the kinetics of testosterone metabolism in postmenopausal women with metastatic breast cancer.
睾酮是一种已知的雌激素前体，尤其在绝经后女性中。他莫昔芬是一种抗雌激素药物，用于治疗已证实有转移性疾病的乳腺癌女性患者。他莫昔芬的作用被认为是占据靶组织中的细胞内雌激素受体位点，从而阻断生物活性雌激素雌二醇的作用。已经推测了他莫昔芬对激素产生和代谢的影响。我们通过在6名绝经后乳腺癌女性患者中持续输注³H-睾酮，研究了他莫昔芬治疗前和治疗期间睾酮代谢的动力学。他莫昔芬对睾酮的代谢清除率、血浆浓度或计算得出的血液生成率没有产生任何显著变化。睾酮向代谢产物转化率的唯一显著改变是向5α-双氢睾酮的转化率降低（p＜0.02）。发现脱氢表雄酮的血浆浓度显著降低（p＜0.05），促黄体生成素的血浆浓度显著降低（p＜0.02）。其他类固醇和肽类激素没有显示出任何显著变化。我们得出结论，他莫昔芬治疗对绝经后转移性乳腺癌女性患者的睾酮代谢动力学影响很小。
