Vidyashankar N, Moudgal N R
Mol Cell Endocrinol. 1984 Sep;37(2):215-22. doi: 10.1016/0303-7207(84)90054-6.
The relative induction of FSH and LH receptors in the granulosa cells of immature rat ovary by pregnant mare serum gonadotropin (PMSG) has been studied. A single injection of PMSG (15 IU) brought about a 3- and 12-fold increase in FSH and LH receptor concentration, respectively, in the granulosa cells. Maximal concentration was reached by 72 h but the receptor levels showed a sharp decline during the next 24-48 h. The kinetic properties of the newly formed FSH receptors were indistinguishable from the pre-existing ones. The induced FSH receptors were functional as demonstrated by an increase in the in vitro responsiveness of the cells to exogenous FSH in terms of progesterone production. Treatment of immature rats with cyanoketone, an inhibitor of delta 5,3 beta-hydroxysteroid dehydrogenase, prior to PMSG injection effectively reduced the PMSG-stimulated increase in the serum estradiol, uterine weight and LH receptors but had no effect on the FSH receptor induction. The ability of PMSG to induce gonadotropin receptors can be arrested at any given time by injecting its antibody, thereby suggesting a continuous need for the hormonal inducer. Estrogen in the absence of the primary inducer was unable to maintain the induced LH and FSH receptor concentration. Inhibition of prostaglandin synthesis using indomethacin aslo had no effect on either the induction or degradation of gonadotropin receptors. Administration of PMSG antiserum, 48 h after PMSG injection, brought about a rapid decline in the induced receptors over the next 24 h, with a rate constant and t 1/2 of 0.078 h-1 and 8.9 h for FSH receptors and 0.086 h-1 and 8.0 h for the LH receptors, respectively.
对孕马血清促性腺激素（PMSG）诱导未成熟大鼠卵巢颗粒细胞中促卵泡激素（FSH）和促黄体生成素（LH）受体的相关情况进行了研究。单次注射PMSG（15国际单位）可使颗粒细胞中FSH和LH受体浓度分别增加3倍和12倍。72小时时达到最大浓度，但在接下来的24 - 48小时内受体水平急剧下降。新形成的FSH受体的动力学特性与预先存在的受体并无差异。从细胞对促性腺激素释放激素（GnRH）的体外反应性（以孕酮生成来衡量）增强这一点可以证明，诱导产生的FSH受体具有功能。在注射PMSG之前，用δ5,3β - 羟基类固醇脱氢酶抑制剂氰基酮处理未成熟大鼠，可有效降低PMSG刺激引起的血清雌二醇、子宫重量和LH受体的增加，但对FSH受体的诱导没有影响。通过注射PMSG抗体，可在任何给定时间阻止PMSG诱导促性腺激素受体，这表明持续需要这种激素诱导剂。在没有主要诱导剂的情况下，雌激素无法维持诱导产生的LH和FSH受体浓度。使用吲哚美辛抑制前列腺素合成对促性腺激素受体的诱导或降解也没有影响。在注射PMSG 48小时后给予PMSG抗血清，在接下来的24小时内诱导产生的受体迅速下降，FSH受体的速率常数和半衰期分别为0.078小时-1和8.9小时，LH受体的速率常数和半衰期分别为0.086小时-1和8.0小时。
