睾酮对β-淀粉样蛋白1-42寡聚体联合去势对大鼠脑内突触后膜致密物-95表达的影响

Effects of testosterone on postsynaptic density protein-95 expression induced by Aβ1-42 oligomers combined with gonadectomy in the rat brain

目的:研究睾酮对β-淀粉样蛋白(Aβ) 1-42寡聚体联合去势大鼠突触可塑性的影响.方法:采用双侧海马CA1区分别注射Aβ1-42寡聚体10 μg联合去势,建立阿尔茨海默病(AD)样动物模型,大鼠随机分为模型对照组、睾酮组、氟他胺组、氟他胺+睾酮组,另设空白对照组.尼氏染色计数各组正常锥体细胞;免疫组织化学和免疫印迹检测各组大鼠脑内突触后膜致密物-95(PSD-95)的表达量.结果:睾酮组细胞计数、PSD-95表达量较高,与空白对照组无差异,但与其余3组差异均存在统计学意义;氟他胺组、氟他胺+睾酮组、模型对照组中神经细胞数量与PSD-95表达量组间均无差异.结论:睾酮对突触可塑性的作用是通过增加细胞存活率与雄激素受体途径实现的.

Objective:To investigate effects of testosterone on synaptic plasticity in rats induced by Aβ1-42 oligomers combined with gonadectomy.Methods:10 μg Aβ1-42 oligomers were injected into both hippocampal CAl regions in rats combined with gonadectomy to establish Alzheimer’s disease(AD)-like models.The models were divided into 4 groups randomly:the model control group,the testosterone group,the flutamide group,and the flutamide with testosterone group(combined administration).A blank control group was established at the same time.In each group,the normal pyramidal cells were counted by Nissl staining;the expression of postsynaptic density protein-95(PSD-95) in the brain was tested by immunohistochemical staining and Western blotting.Results:There were significantly more normal pyramidal cells and higher expression of PSD-95 in the testosterone group than the other 3 groups(P <0.05),but no significant difference from the blank control group.There was no significant difference in the amount of neurocytes and PSD-95 expression level between the flutamide group,the flutamide with testosterone group and the model control group.Conclusion:The effects of testosterone on synaptic plasticity are realized by increasing androgen receptors and the cell survival rate.