雌激素对老年大鼠小脑ER、ChAT、NGF表达的影响

Effects of Estrogen on ER, NGF and ChAT Expression in Cerebellum of Aging Female Sprague-Dawley Rat

【目的】探讨雌激素对大鼠小脑内雌激素受体(ER)、神经生长因子(NGF)和胆碱乙酰转移酶(ChAT)表达的影响。【方法】运用超敏感的免疫组织化学SP法,以老年SD大鼠小脑为研究对象,通过补充17β-雌二醇对ER、NGF和ChAT在小脑中的表达和分布变化进行研究。【结果】ER、NGF和ChAT免疫阳性反应物分布于小脑的蒲肯野氏细胞层、小脑齿状核、小脑间位核和小脑室顶核,ER阳性产物主要定位于细胞胞浆和突起中,也存在于胞膜和胞核中。老年大鼠小脑皮质及小脑核中ER、NGF和ChAT的表达强度及阳性细胞数量总趋势是显著降低,而补充17β-雌二醇后三种阳性产物的强度和阳性细胞数目显著回升,蒲肯野氏细胞的阳性突起长度和数量也呈此变化趋势。【结论】雌激素可促进NGF和ChAT的表达,在维持和保护小脑神经元的结构和功能中发挥了重要作用;另外ER、NGF和ChAT表达变化的相似性提示三者在雌激素对小脑的作用中是相互调节和影响的,同时表明雌激素在小脑发挥作用可能既通过基因组机制,也通过非基因组机制途径。

[ Objective ] The effects of estrogen on the expression of ER, NGF and ChAT in cerebellum of rats were studied. [Method] The model of aging female rat were established to study the expression and distribution of estrogen receptor （ER）, nerve growth factor （NGF） and choline acetyltransferase （CHAT） in the cerebellum after 17β-estradiol treatment by using technique of immunohistochemical ultrasensitive SP in Sprague-Dawley rat. [Result] The immunoreactive productions were distributed in stratum Purkinje cell, nucleus dentatus, nucleus interpositus and nucleus fastigii of cerebellum, and the ER positive production mainly located in plasma, cytoplasmic membrane and neurite, also existed in nucleus. The general tendency of the expression of ER, NGF and ChAT positive production in cerebellum cortex and nuclei of aging rat significantly decreased, while the intensity and quantity of the immunoreactive production ascended predominantly after 17β-estradiol treatment, simultaneously, the positive neurite of Purkinje cell showed the same tendency. [ Conclusion ] The above results suggested that the estrogen upregulated the expression of NGF and CHAT, and played a vital role in sustaining and protecting the structure and function of cerebellum neurons. Furthermore, the similarity of their changing tendency implied that they were correlated and cooperated during the course in effect of estrogen in cerebellum, it also showed that the action of estrogen in cerebellum could via genomic and nongenomic mechanism.