帕金森病大鼠Caspase-8及TH蛋白表达的相关性实验研究

目的利用动物模型探讨Caspase-8和TH蛋白表达与帕金森病(Parkinson disease,PD)的关系。方法60只SD大鼠随机分为两组,大鼠帕金森病模型组:随机分3、7、14、21、28d五组,均通过脑立体定向注入6-羟多巴,均在处死前腹腔注入阿卟吗啡观察30分钟大鼠旋转的次数,连续至第四周每分钟大于6次者为成功的帕金森氏病模型;正常对照组:立体定向注入抗坏血酸生理盐水。处死后制作石蜡切片用免疫组化法检测Caspase-8、酪氨酸羟化酶(TH)蛋白的阳性细胞数。结果纹状体和黑质神经细胞存在细胞凋亡,与对照组存在显著性差异,且Caspase-8蛋白表达在大鼠纹状体和黑质中细胞3d组为最高,其后很快下降,但显著高于对照组。而TH蛋白表达在大鼠纹状体和黑质细胞中对照组为最高,在PD组很快下降,但显著低于对照组。TH蛋白表达减少及Caspase-8蛋白表达增加呈正相关。结论6-OHDA能诱发大鼠黑质细胞凋亡,Caspase-8蛋白表达是帕金森病动物模型发病机制的重要启动因素。

Experimental study on the expression of Caspase-8 and TH in PD rats

Objective:To investigate the relationship between the expression of Caspase-8 protein and Parkinson's disease(PD) in rat models.Methods:Sixty healthy male Sprague-Dawley rats were divided into two groups.First group of fifty rats were Parkinson disease models in rats(PD group),subdivided into groups of 3d,7d,14d,21d,28d.They were prepared to be hemiparkinsonian models induced by unilateral stereotaxic infusion of 6-hydroxydopamine(6-OHDA) in right substantia nigra of midbrain.Every week after operation,circles the rats run in 30 minutes were observed after injecting apomorphine by peritoneal cavity.If the rat ran more than 6 circles every minute at the fourth week after operation,they were successful PD rat models.The second group of the ten rats was jnjected natrium saline and served as a control group.The rats were executed and slices were made.Finally,the expression of Caspase-8 and TH protein through immunohistochemistry(IH) were compared,according to further discuss death receptor pathways access at disease pathogenesis nesne action.Results: Compared with the control group,in the groups from that of 3d to the 28d,the number of Caspase-8 positive cells in sustantia nigra and striatum of rats in PD group increased significantly.In the PD group the Caspase-8 protein attained the peak value promptly at 3d,and then decreased gradually.On the other hand,TH protein in the control group exceeded that of the PD group.From the group of 3d to the 28d the number of TH positive cells in sustantia nigra and striatum of rats in PD group decreased significantly.In the control group the TH protein attained the peak value.Conclusion: The apoptosis of substantia nigra and striatum can be evoked by 6-OHDA.Apoptosis of substantia nigral induced by 6-OHDA contributes to the pathogenesis of PD.As a start key evoking factor,Caspase-8 protein involves in pathogenesis of Parkinson disease.