Division of Clinical and Molecular Endocrinology, Case Western Reserve University, Case Medical Center, 11100 Euclid Ave., Cleveland, OH 44106, USA.
Best Pract Res Clin Endocrinol Metab. 2009 Dec;23(6):769-80. doi: 10.1016/j.beem.2009.06.005.
Thyroid function is modulated by genetic and environmental causes as well as other illnesses and medications such as gonadal or sex steroids. The latter class of drugs (sex steroids) modulates thyroid function. Gonadal steroids exert their influence on thyroid function primarily by altering the clearance of thyroxine-binding globulin (TBG). While oestrogen administration causes an increase in serum TBG concentration, androgen therapy results in a decrease in this binding protein. These effects of gonadal steroids on TBG clearance and concentration are modulated by the chemical structure of the steroid being used, its dose and the route of administration. Despite the gonadal steroids-induced changes in serum TBG concentrations, subjects with normal thyroid glands maintain clinical and biochemical euthyroidism without changes in their serum free thyroxine (T4) or thyroid-stimulating hormone (TSH) levels. In contrast, the administration of gonadal steroids to patients with thyroid diseases causes significant biochemical and clinical alterations requiring changes in the doses of thyroid medications. Similarly, gonadal steroid therapy might unmask thyroid illness in previously undiagnosed subjects. It would be prudent to assess thyroid function in subjects with thyroid disease 6-8 weeks after gonadal steroid administration or withdrawal.
甲状腺功能受遗传和环境因素以及其他疾病和药物（如性腺或性激素）的调节。后一类药物（性激素）调节甲状腺功能。性腺类固醇主要通过改变甲状腺素结合球蛋白（TBG）的清除率来发挥其对甲状腺功能的影响。虽然雌激素的使用会导致血清 TBG 浓度升高，但雄激素治疗会导致这种结合蛋白减少。性腺类固醇对 TBG 清除率和浓度的这些影响受所用类固醇的化学结构、剂量和给药途径的调节。尽管性腺类固醇会导致血清 TBG 浓度发生变化，但甲状腺功能正常的患者在血清游离甲状腺素（T4）或促甲状腺激素（TSH）水平没有变化的情况下仍保持临床和生化甲状腺功能正常。相反，性腺类固醇的给药会导致甲状腺疾病患者出现显著的生化和临床改变，需要改变甲状腺药物的剂量。同样，性腺类固醇治疗可能会在以前未被诊断的患者中揭示甲状腺疾病。在性腺类固醇给药或停药后 6-8 周，评估甲状腺功能是谨慎的做法。
