Köves K, Kerdelhué B, Molnár J, Csernus V, Halász B
2nd Department of Anatomy, Semmelweis Medical University, Budapest, Hungary.
Neuroendocrinology. 1988 Nov;48(5):489-94. doi: 10.1159/000125054.
Pituitary gonadotropin-releasing hormone (GnRH) binding sites were studied in persistent estrous rats. For comparison females at different stages of the estrous cycle, ovariectomized animals, and intact males were examined. Persistent estrus was induced by a hypothalamic knife cut, administering testosterone to neonatal rats, or by constant illumination. Rats showing spontaneously such alteration were also used in the experiment. Besides pituitary GnRH-binding sites, the GnRH content of the median eminence and plasma luteinizing hormone, follicle-stimulating hormone, estradiol, and progesterone concentrations were determined. Pituitary GnRH receptors changed during the estrous cycle with the highest concentrations observed on proestrus. In rats in persistent estrus, pituitary GnRH-binding sites varied between proestrous and estrous values of cyclic females. Ovariectomy resulted in a significant increase in receptors. Depending on how the persistent estrous syndrome was induced, very different amounts of GnRH were found in the median eminence of the various groups. Our data indicate that the GnRH-binding sites on pituitary cells of persistent estrous rats are in essence not changed.
研究了持续性发情大鼠垂体促性腺激素释放激素（GnRH）结合位点。为作比较，还检测了处于发情周期不同阶段的雌性大鼠、去卵巢动物和完整雄性大鼠。通过下丘脑刀割、给新生大鼠注射睾酮或持续光照诱导持续性发情。实验中也使用了自发出现这种改变的大鼠。除了垂体GnRH结合位点外，还测定了正中隆起的GnRH含量以及血浆促黄体生成素、促卵泡激素、雌二醇和孕酮浓度。垂体GnRH受体在发情周期中发生变化，在发情前期观察到最高浓度。在持续性发情大鼠中，垂体GnRH结合位点在发情周期雌性大鼠的发情前期和发情期值之间变化。去卵巢导致受体显著增加。根据持续性发情综合征的诱导方式不同，在各个组的正中隆起中发现了非常不同量的GnRH。我们的数据表明，持续性发情大鼠垂体细胞上的GnRH结合位点本质上没有变化。
