下丘脑弓状核瘦素/瘦素受体-吻素/吻素受体系统对大鼠卵泡发育的影响

Effects of the leptin/leptinr-kisspeptin/kisslr system on the development of ovarian follicles in puberty rats

摘要目的：探讨青春期前后瘦素／瘦素受体-吻素／吻素受体（1eptin／leptinr-kisspeptin／kisslr）系统的表达及其对卵泡发育的影响。方法：取青春期前期和青春期雌性Wistar大鼠，H—E染色观察卵巢形态学，ELISA法测血清leptin、雌二醇（E2）、卵泡刺激素（FSH）、黄体生成素（LH）水平，QT-PCR、免疫组织化学和免疫印迹分别检测下丘脑弓状核leptinr、kisspeptin／kisslr、GnRHmRNA及其蛋白的表达。结果：青春期前期大鼠卵巢中有大量初级卵泡和少量次级卵泡，青春期后除初级卵泡外，次级卵泡数量增加。青春期与青春期前期相比，血清岛、LH、leptin、FSH升高明显。青春期leptinr-、kiss1-、kisslr-和Gnrh—mRNA水平分别是青春期前期的0．82、1．43、1．33、1．37倍。免疫组织化学及免疫印迹结果显示，leptinr表达于细胞核，青春期leptinr表达低于青春期前期；kisspeptin／kisslr、促性腺激素释放激素（GnRH）在下丘脑弓状核的胞质表达，青春期kisspeptin／kisslr、GnRH表达高于青春期前期。结论：雌性大鼠下丘脑弓状核kisspeptin／kissh系统对青春期卵泡发育发挥启动作用，kisspeptin／kisslr可能介导leptin／leptinr与GnRH之间的相互作用。

Objective： To explore the expressions of leptin/leptinr-kisspeptin/kisslr system and their effects on the development of ovarian follicles in puberty Wistar rats. Methods： Female Wistar rats selected from prepuberty and puberty periods were divided into two groups. Ovarian morphological changes were observed by H-E staining. ELISA, QT-PCR, immunohistochemistry and Western blotting were used to determine the contents of leptin, F4, FSH and LH in the serum, gene levels and protein expressions of leptinr, kisspeptin, kisslr and GnRH in the arcuate nucleus of hypothalamus, respectively. Results： There were many primary follicles and few secondary follicles in the ovaries of the prepuberty rats and the number of secondary follicles increased in the puberty rats. The serum levels of F4, LH of the puberty rats increased compared with that of the prepuberty rats, and the level of leptin, FSH increased markedly. Compared with the prepuberty rats, the gene levels of kisspeptin, kisslr and Gnrh in the hypothalamic arcuate nucleus increased, while the level of leptinr mRNA decreased. In puberty rats, kisspeptin, kisslr and GnRH expressed in cytoplasm of the hypothalamic arcuate nucleus and the levels were higher than those of the prepuberty rats, while leptinr located in the nucleus and its level decreased. Conclusion： The kisspeptin/kisslr system of the hypothalamic arcuate nucleus in puberty female rats plays important roles in the development of ovarian follicles, and this system may mediate the interaction of leptin/leptinr and GnRH.