摘要
目的 :在细胞和分子水平上 ,探讨机体因各种原因导致卵巢功能低下时 ,下丘脑 垂体 卵巢轴 (HPOA)功能的自然代偿机制。 方法 :观察大鼠切除卵巢后 1～ 6个月 ,下丘脑促性腺激素释放激素 (Gonadotropinreleasinghormone ,GnRH)及其mRNA表达的改变以及阴道脱落细胞形态和外周血雌二醇 (E2 )水平的变化。结果 :去卵巢后 5～ 6个月时 ,大鼠阴道涂片出现成熟脱落细胞 ;4个月时血E2 水平明显升高 ,6个月时几乎稳定在正常水平的一半以上 ;随去卵巢时间延长 ,大鼠下丘脑GnRH神经元数目较去卵巢 1个月时逐渐增多 ,至 6个月时 ,升高有显著差异 ,但仍低于正常组数目 ;去卵巢 1个月大鼠下丘脑组织GnRHmRNA表达明显减少 ,去卵巢后 5个月明显升高 ,与正常组相比没有显著差异 ;GnRH棘型神经元的比例在去卵巢 4个月时即升高到正常水平。 结论 :大鼠卵巢功能低下时 ,机体体内可能存在一种自然代偿作用 ,使异常的HPOA功能趋于正常化。
Objective: By observing the changes of vaginal epithelium cells, blood estrogen (E 2 ) level, also hypothalamic GnRH and its mRNA expressions of the rats 1 6 months after ovariectomy, to explore the cellular and molecular compensational mechanism under the condition of hypofunction of hypothalamus pituitary ovary axis. Methods: Puberty female rats were divided into intact group (INT) and ovariectomy group (OVX). Radioimmunoassay was used to determine the blood content of E 2 . Immunohistochemistry was used to observe the number and morphological change of hypothalamic GnRH immuno positive neurons. Semi quantitative RT PCR was used to test hypothalamic GnRH mRNA expression. Results: After ovariectomy, the blood E 2 in rats was hardly detected in 1 month but increased significantly 4 months later, and reached nearly half of the normal level in 6 months. The number of hypothalamic GnRH neurons decreased significantly in 1 month while it increased in 4 6 months, though disparity still existed between OVX 6 months and INT groups. The level of hypothalamic GnRH mRNA decreased in 1 month and increased in 5 months and there was no disparity between OVX 5,6 months groups and INT group; the proportion of spiny GnRH neurons in rats of OVX 4,5,6 months increased to the level of intact group. Conclusion: There may be intrinsic functional compensation for the hypofunction of hypothalamus pituitary ovary axis due to ovariectomy. \[
基金
国家自然科学基金资助课题 ( 3 9870 914 )
上海市卫生局中医药重大课题 ( 2 0 0 0 3 )
