ROLE FOR HYPOTHALAMIC ADRENERGIC RECEPTORS IN PREOVULATORY LH SURGE

性交引起下丘脑去甲肾上腺素（NE）增加 在排卵前几分钟发生的分泌物 促性腺激素释放激素（GnRH）/促黄体生成激素激增 （LH）. 评估NE与GnRH/LH之间的因果关系 在性交过程中释放，我们试图阻止性交引起的 通过下丘脑内（ih）输注`-肾上腺素能 受体阻滞剂哌唑嗪。 对完整的雌性家兔进行了以下处理： 推拉式灌注7 h，连续10 min样本采集 用于灌注液GnRH和血液LH测量。 与雄性交配 伴侣发生在第三小时，持续ih哌唑嗪， 在2小时到7小时之间。 目前的数据显示， 哌唑嗪处理组的GnRH/LH释放较低， 与对照组相比，女性。 然而，哌唑嗪 没有完全消除GnRH/LH对性交的反应。 本 最后，至少有三种解释可以提供（1）NE不是 唯一决定性交诱导的GnRH/LH峰的因素，（2）NE可能 也通过位于外的肾上腺素能受体刺激GnRH 下丘脑内侧基底部，和（3）哌唑嗪的剂量可能是 不足以阻断中基底面内的所有肾上腺素能受体 下丘脑 我们继续探讨这些问题。 最终 研究结果将有助于了解生育期间的大脑功能， 不育的生殖阶段。

Coitus induces an increase in hypothalamic norepinephrine (NE) secretion that occurs several minutes prior to a preovulatory-like surge of gonadotropin-releasing hormone (GnRH)/luteinizing hormone (LH). To assess the causal relationship between NE and GnRH/LH release during coitus, we attempted to block the coitus-induced GnRH/LH surge by intrahypothalamic (ih) infusion of an `-adrenergic receptor blocker, prazosin. Intact female rabbits were subjected to push-pull perfusion for 7 h with continuous 10-min sample collections for perfusate GnRH and blood LH measurements. Mating with male partners occurred at the third hour and continuous ih prazosin was given between hours 2 and 7. Present data show that the magnitude of the coitus-induced GnRH/LH release was lower in prazosin-treated females as compared to that in the control group. However, prazosin did not completely abolish the GnRH/LH response to coitus. To this end, at least three interpretations can be offered (1) NE is not the only factor determining the coitus-induced GnRH/LH surge, (2) NE may also stimulate GnRH via `-adrenergic receptors located outside the mediobasal hypothalamus, and (3) the dosage of prazosin may be insufficient to block all `-adrenergic receptors within the mediobasal hypothalamus. We continue to explore these issues. Ultimately, the findings will aid understanding of brain functions during fertile and infertile reproductive stages.