哺乳期雌性大鼠下丘脑内促性腺激素释放激素神经元的免疫组织化学研究

IMMUNOHISTOCHEMICAL STUDY OF CHANGES OF GONADOTROPHIN-RELEASING HORMONE NEURONS IN RAT HYPOTHALAMUSDURING LACTATION

采用免疫组织化学方法研究了产后授乳和中断授乳的雌性大鼠下丘脑内促性腺激素释放激素(GnRH)阳性神经元和神经纤维的密度和染色反应的变化.在哺乳的第3天,将半数母鼠的仔鼠去除,中断授乳后1～4天下丘脑内侧隔核、视前内侧区和Broca斜角带内的GnRH阳性神经元胞体的反应强度明显高于继续授乳组.在正中隆起和终板血管器的GnRH阳性纤维和终末的密度和染色强度也比授乳组明显增加.结果表明:中断授乳的母鼠下丘脑内GnRH分泌神经元激素的合成和释放功能均明施增强,而哺乳对下丘脑内GnRH神经元的合成和释放激素的功能有显著的抑制作用.

Changes of the density and staining reaction of GnRH-immunoreactive neurons in rathypothalamus were studied by immunohistochemical method during lactation and after weaning. Thelitters were removed on the 3rd day of lactation, 1-4 days after which a significant increase of thestaining intensity of GnRH-immunoreactive neurons in the medial septal area, medial preopticarea and diagonad band of Broca were observed. The density and staining intensity of GnRH fibersand terminals in median eminence and organum vasculosum of the lamina terminalis were alsopronounced. The results indicated that the secretion and releasing of GnRH neurons increased afterweaning, while the sucking of the litter exerted an inhibitary effect on the secretion and releasingof GnRH neurons in rat hypothalamus.