Cho B N, Seong J Y, Cho H, Kim K
Department of Molecular Biology and SRC for Cell Differentiation, College of Natural Sciences, Seoul National University, South Korea.
Brain Res. 1994 Jul 25;652(1):177-80. doi: 10.1016/0006-8993(94)90336-0.
Gonadotropin-releasing hormone (GnRH) is a major neural signal for hypothalamic control of gonadotropin secretion which in turn influences gonadal steroid synthesis. Progesterone (P) is known to affect release and content of GnRH. The action mechanism of P on GnRH mRNA level remains, however, to be resolved. Here we report that P augments GnRH mRNA level in hypothalamic tissues derived from ovariectomized, estradiol-treated adult rats. The stimulatory action of P was time-dependent and lasted at least for 9 h. When RU486, a P receptor antagonist, was administered 1 hr before P treatment, it clearly blocked the stimulatory action of P on GnRH mRNA level. These results strongly suggest that P regulates GnRH gene expression in the rat hypothalamus, presumably through the P receptor-mediated mechanism.
促性腺激素释放激素（GnRH）是下丘脑控制促性腺激素分泌的主要神经信号，促性腺激素分泌进而影响性腺甾体合成。已知孕酮（P）会影响GnRH的释放和含量。然而，P对GnRH mRNA水平的作用机制仍有待阐明。在此我们报告，P可提高来自去卵巢、经雌二醇处理的成年大鼠下丘脑组织中的GnRH mRNA水平。P的刺激作用具有时间依赖性，且至少持续9小时。当在P处理前1小时给予P受体拮抗剂RU486时，它明显阻断了P对GnRH mRNA水平的刺激作用。这些结果强烈表明，P可能通过P受体介导的机制调节大鼠下丘脑GnRH基因的表达。
