重复制动应激对雌性大鼠下丘脑-垂体-卵巢轴的影响

目的: 探索重复制动应激对雌性大鼠下丘脑-垂体-卵巢轴的影响。方法: 40只SD雌鼠随机分为两组(n=20),对照组和实验组,一组正常饲养,一组采取递增负荷束缚应激,每天置于束缚器内制动应激一次(从上午9:00开始),第1日制动2 h,以后采用递增负荷,每日增加0.5 h,持续两周,通过检测体重、脏器系数、动情周期、性激素、病理和相关基因的表达探索其对下丘脑-垂体-卵巢轴的危害。结果: 重复制动应激使雌性大鼠体重下降、动情周期延长,卵巢和子宫的脏器系数和形态发生改变,利用qPCR技术对其相关基因检测,发现下丘脑促性腺激素释放激素、垂体促性腺激素释放激素受体、促卵泡生成素和促黄体生成素mRNA的表达显著下降,卵巢促卵泡生成素和黄体生成素受体 mRNA的表达显著上升,卵巢和子宫雌激素受体mRNA的表达显著下降。结论: 重复制动应激可能通过干扰下丘脑-垂体-卵巢轴的内分泌调节作用,使动情周期紊乱,从而损伤雌性动物的性腺和生殖内分泌功能。

Effects of repeated immobilization stress on hypothalamic-pituitary- ovarian axis in female rats

Objective: To explore the effects of repeated immobilization stress on hypothalamic-pituitary-ovarian axis in female rats. Methods: Forty female SD rats were randomly divided into two groups: control group (n=20) and experimental group (n=20). One group was fed normally, the other group was subjected to incremental load restraint stress. Brake stress once a day in the retainer (starting at 9: 00 a.m.), braking for 2 hours on the first day, increasing load by 0.5 hours a day for two weeks. Body weight, estrous cycle, sex hormone, organ coefficient, pathology and expression of related genes were detected to explore the harm of hypothalamic-pituitary-ovarian axis. Results: Repeated immobilization stress caused weight loss, prolonged estrous cycle, and changed the organ coefficient and morphology of ovaries and uterus. QPCR technique was used to detect the related genes. It was found that the expressions of gonadotropin releasing hormone, pituitary gonadotropin releasing hormone receptor, follicle stimulating hormone and luteinizing hormone mRNA were decreased significantly, while the expressions of ovarian follicle stimulating hormone and luteinizing hormone receptor mRNA were increased significantly. The expression of estrogen receptor mRNA in ovary and uterus was decreased significantly. Conclusion: Repeated immobilization stress may disrupt the estrous cycle by interfering with the endocrine regulation of the hypothalamic-pituitary-ovarian axis, thus damaging the gonadal and reproductive endocrine function of female animals.