肿瘤坏死因子α在帕金森病模型鼠纹状体中的表达

Expression of tumor necrosis factor alpha in striatum of model rats with Parkinson disease

目的:探讨前炎性细胞因子肿瘤坏死因子在帕金森病模型大鼠发病中的作用。方法:实验于2004-02/04在吉林大学第二医院动物实验室完成。将50只Wistar大鼠,随机分为模型组(n=26)、生理盐水组(n=12)和正常对照组(n=12)。将5μL神经毒素6-羟基多巴(2g/L)立体定向术注入大鼠右侧纹状体内,制备帕金森病模型,生理盐水组以等量的生理盐水代替,正常对照组不干预。术后2周开始检测由阿朴吗啡诱发的旋转行为(向左侧旋转速度大于7r/min为模型成功的标志)。术后2个月每组取2只鼠行病理切片观察黑质多巴胺能神经元的改变及肿瘤坏死因子α的表达,每组取10只鼠采用酶联免疫吸附法检测纹状体内肿瘤坏死因子α的含量。结果:36只大鼠进入结果分析。①造模组造模成功有18只。模型组右侧黑质致密区内多巴胺能神经元几乎消失,残存细胞萎缩;右侧黑质和纹状体内均有肿瘤坏死因子α的阳性表达,且主要分布在激活的小胶质细胞上。②纹状体内肿瘤坏死因子α的含量:模型组右侧显著高于左侧[(3.853±0.364),(2.891±0.306)ng/g,t=2.391,P<0.05];也显著高于正常对照组和生理盐水组右侧[(2.721±0.446),(2.960±0.341)ng/g,P<0.05]。结论:肿瘤坏死因子α参与了6-羟基多巴胺导致的多巴胺能神经元死亡的过程。帕金森病大鼠模型的发病机制中有炎症因子的参与,氧化应激与炎性作用机制可能密切相关。

AIM： To investigate the role of the proinflammatory cytokine, tumor necrosis factor alpha（TNF-α） in the episode of Parkinson disease in the rat models. METHODS： The experiment was completed in the laboratory for animals, Second Hospital, Jilin University from February to April 2004. Fifty Wistar rats were randomly divided into three groups： animal model group （n=26）,normal saline group （n=12） and normal control group （n=12）. The 5μL neurotoxin,6-hydroxydopamine（6-OHDA, 2 g/L） was stereotaxically injected into the right striatum of rats at two sites to induce Parkinson disease. The rats in the normal saline group received the same volume of normal saline, and those in the normal control group were not treated. The apomorphineinduced rotational behavior （left rotation speed faster than 7 rotations per minute as the success marker of modeling） was tested two weeks after the operation. Changes of dopaminergic neuron in substantia nigra region and expression of TNF-α were observed in 2 rats of each group at 2 months after operation, and the level of TNF-α in the striatum of l0 rats in each group was measured by enzyme-linked immunosorbent assay（ELISA）. RESULTS： All the 36 rats were analyzed in the result. ①Eighteen rats of the model group were successful Parkinson disease models. The dopaminergic neurons in the dense right substantia nigra region disappeared nearly, and the surviving ones were atrophic in the model group. The expression of TNF-α was positive in the right striarum and right substantia nigra, and distributed mainly on the activated mierogliocytes in the model group. ②The level of TNF-α in the right striatal regions were significantly higher than that in the left side in the model group[（3.853±0.364）ng/g vs （2.91 ±0.306）ng/g, t=2.391, P 〈 0.05], and also significantly higher than that in the right striatal regions in normal control group[（2.721±0.446）ng/g] and in the normal saline group[（2.960±0.341）ng/d （both P 〈 0.05）. CONCLUSION： TNF-α participates in the 6-OHDA-inducod death of dopaminergic neurons. Inflammatory cytokines participate in the pathogenesis of Parkinson disease of rats. Oxidative stress may in a close relationship with inflammatory pathogenesis.