Okatani Y, Fishman J
Neuroendocrinology. 1986;44(2):190-4. doi: 10.1159/000124644.
Cycling rats injected with 2-hydroxyestrone or 2-hydroxyestradiol at 09.00 or 10.00 h in the morning of proestrus do not express the normal preovulatory LH surge in the afternoon of the day. The LHRH content of the median eminence in control animals decreases sharply in the afternoon from elevated noon and morning levels. The catechol estrogen-treated rats fail to show the decrease. Thus the catechol estrogens block the LH surge at its usual time by influencing the changes in the concentration of LHRH in the median eminence on proestrus. Since the catechol estrogens have short biological half-lives, their effect on the LHRH content in the afternoon must originate in the morning at the time of the endogenous estradiol (E2) peak. These results have implications in the physiological processes responsible for the positive feedback of estradiol on the preovulatory LH surge in the rat.
在动情前期的上午9点或10点注射2-羟基雌酮或2-羟基雌二醇的骑乘大鼠，在当天下午不会出现正常的排卵前促黄体生成素（LH）激增。对照动物正中隆起的促性腺激素释放激素（LHRH）含量在下午从中午和上午升高的水平急剧下降。接受儿茶酚雌激素处理的大鼠没有出现这种下降。因此，儿茶酚雌激素通过影响动情前期正中隆起中LHRH浓度的变化，在其通常的时间阻断LH激增。由于儿茶酚雌激素的生物半衰期较短，它们对下午LHRH含量的影响必定源于上午内源性雌二醇（E2）峰值出现的时候。这些结果对大鼠排卵前LH激增中雌二醇正反馈所涉及的生理过程具有启示意义。
