INVOLVEMENT OF ESTROGENS IN THE REGULATION OF GRANULOSA-CELL AROMATASE-ACTIVITY
INVOLVEMENT OF ESTROGENS IN THE REGULATION OF GRANULOSA-CELL AROMATASE-ACTIVITY
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DOI：
10.1139/y83-077
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发表时间：
1983-01-01
影响因子：
2.1
通讯作者：
ARMSTRONG, DT
中科院分区：
文献类型：
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作者：
DANIEL, SAJ;ARMSTRONG, DT
雄激素增强FSH诱导的未成熟大鼠卵巢颗粒细胞芳香化酶活性;然而，芳香化雄激素比非芳香化雄激素更有效。研究了雄激素芳构化为雌激素是可芳构化雄激素更有效的原因。在36小时的诱导期内，在FSH、FSH +睾酮或FSH +双氢睾酮的存在下，在有或没有芳香化酶活性抑制剂4-乙酰氧基-4-雄烯-3，17-二酮（4-乙酰氧基-A）的情况下培养颗粒细胞。用雄激素处理增强芳香酶活性，测量为雌二醇-17 β的积累。在6小时的试验期间，加入睾酮作为底物。这两种雄激素对FSH诱导的芳香化酶活性的影响被4-乙酰氧基-A阻断。在诱导期存在高浓度的己烯雌酚（DES）（一种合成雌激素）对FSH诱导的雌二醇-17 β具有显著的积极作用。在测试期间积累。所有较低剂量均无效。萘福昔定，一种抗雌激素，已知抑制雌激素结合其细胞内受体，对睾酮增强FSH诱导的芳香化酶没有影响。颗粒细胞在培养中合成的雌激素显然只是部分负责睾酮的能力更大，以提高FSH诱导的芳香化酶活性相比，双氢睾酮（DHT）。其他因素，如雄激素代谢和受体亲和力的差异率可能是雄激素效力的主要决定因素。
Androgens enhance FSH induced aromatase activity in cultured granulosa cells obtained from the ovaries of immature rats; however, aromatizable androgens are more effective than nonaromatizable androgens. That aromatization of androgens to estrogens is responsible for the greater effectiveness of aromatizable androgens was studied. Granulosa cells were cultured during a 36-h induction period in the presence of FSH, FSH + testosterone, or FSH + dihydrotestosterone with or without 4-acetoxy-4-androstene-3,17-dione (4-acetoxy-A), an inhibitor of aromatase activity. Treatment with androgens enhanced aromatase activity measured as accumulation of estradiol-17.beta. during a 6-h test period with testosterone added as substrate. The effects of both androgens on FSH-induced aromatase activity were blocked by 4-acetoxy-A. Presence of a high concentration of diethylstilbestrol (DES), a synthetic estrogen, during the induction period had a significant positive effect on FSH-induced estradiol-17.beta. accumulation during the test period. All lower doses were ineffective. Nafoxidine, an antiestrogen known to inhibit binding of estrogens to their intracellular receptors, had no effect on enhancement of FSH-induced aromatase by testosterone. Estrogens synthesized by granulosa cells in culture are apparently only partially responsible for the greater ability of testosterone to enhance FSH-induced aromatase activity compared with that of dihydrotestosterone (DHT). Other factors such as differential rates of androgen metabolism and receptor affinities are probably the major determinants of androgen potency.