氯化锂对帕金森病小鼠黑质多巴胺能神经元保护作用的实验研究

The protection of lithium chloride over the DA neurons in PD mice

目的研究氯化锂(LiCl)对KM小鼠中脑黑质受损伤的多巴胺(DA)能神经元的保护作用。方法利用1-甲基4-苯基1,2,3,6四氢吡啶(MPTP)腹腔注射构建帕金森病(PD)动物模型,将实验动物分为MPTP组、NS组(生理盐水组)、LiCl组、PBS组(磷酸盐生理盐水缓冲液组)。模型动物存活1周后,一部分取其中脑黑质节段,固定、包埋做连续冠状石蜡切片,以免疫组织化学染色方法,显示各组酪氨酸羟化酶(TH)和钙结合蛋白(CB)表达阳性细胞,光镜观察并细胞计数,统计学分析;另一部分取其中脑黑质组织匀浆,行TH、CB的Western blot免疫印迹方法检测,用LabWorks软件分析处理。结果免疫组织化学染色结果显示LiCl组、NS组小鼠黑质致密部TH与CB阳性神经元数量分别显著多于PBS组(P<0.01)、MPTP组(P<0.01);Western blot免疫印迹结果显示LiCl组TH、CB表达水平显著高于PBS组(P<0.05)。结论LiCl对成年PD小鼠黑质DA能神经元具有保护作用,且这种保护作用可能与细胞内CB表达增加有关。

Objective To study the protective effect of lithium chloride on dopaminergic （DA） neurons in the substantia nigra （SN） of MPTP- induced mouse model of Parkinson disease （PD）. Methods The PD model was induced in adult KM mice by intraperitoneal injection of MPIP. The mice models were divided into four groups. After varied survival periods, the model mice were sacrificed to get the specimens of SN fixed, embedded and coronally sectioned continuously. The microsections were processed by immunohistochemistry to label the DA neurons and Calbindin D28k （CB） - containing neurons with the antibodies against tyrosine hydroxylase （TH） and CB respectively. The labeled cells were counted under microscope and analyzed statistically. Western blot assay was used to determine the protein expression of TH and CB in the SN of mice, Results Following the injection of lithium chloride ip, the densities of TH and CB positive neurons and the protein expressions of TH and CB became significantly higher （ P 〈 0.01 and 〈 0,05）, Conclusion Lithium chloride can protect DA neurons, likely via the increase of CB expression.