黑质内炎症反应对恒河猴多巴胺能神经元的毒性作用  

Neurotoxic effects of inflammation on dopaminergic neurons in the substantia nigra in the rhesus

作　　者：户乃丽[1] 刘玉军[1] 徐群渊[1] 张进禄[1] 

机构地区：[1]首都医科大学北京神经科学研究所北京市神经再生修复研究重点实验室教育部神经变性病学重点实验室,北京100069

出　　处：《解剖学报》2009年第5期732-736,共5页Acta Anatomica Sinica

基　　金：北京市自然科学基金资助项目(7062008);北京市优秀人才资助项目(20042D050182)

摘　　要：目的观察恒河猴黑质内脂多糖注射对多巴胺能神经元的损伤和小胶质细胞的激活以及炎性因子的释放情况,探讨脑内炎症反应在黑质多巴胺能神经元变性过程中的作用。方法成年恒河猴8只,分为急性实验组(3只)与慢性实验组(5只)。急性组单侧黑质脂多糖注射后存活1周。通过免疫印迹方法观察酪氨酸羟化酶(TH)表达量变化与炎性因子的释放情况。慢性组按注射后存活时间及注射药物的不同分为脂多糖注射后存活24周、48周和生理盐水注射后存活48周。上述5只动物于存活前0周、8周、16周,向右侧黑质分3次注射脂多糖或生理盐水。术后用免疫组织化学染色及高效液相色谱法观察黑质TH阳性神经元的变化和纹状体神经递质含量的改变。结果急性实验组注射侧与对照侧TH表达量无明显差异,但注射侧可见小胶质细胞活化,人类白细胞DR抗原表达量上调并有大量肿瘤坏死因子α、白介素1β、环氧化酶2(COX-2)生成。慢性实验组单侧黑质脂多糖注射24周和48周后,各个动物注射侧黑质阳性神经元数量以及纹状体神经递质含量有不同程度的减少,而生理盐水注射动物无变化。结论脂多糖注射后在1周内可引起黑质剧烈的炎症反应,但这种病理过程并不伴随大量多巴胺能神经元死亡。随病程的发展,炎症反应能引起恒河猴黑质多巴胺能神经元慢性进行性的损伤。该病理过程较好模拟了帕金森病的发病特点。Objective To observe the neurodegenerative effects of inflammation, induced by intra-cerebral injection of lipopolysaccharide （LPS） on dopaminergic neurons in the substantia nigra of rhesus monkey, in order to explore the relations of mechanism of Parkinsonism with activation of microglia and the releasing of inflammatory factors in the animal brain. Methods Eight adult rhesus monkeys were divided into an acute experimental group and a chronic experimental group. Among them 3 monkeys were used for acute experiment. They were unilaterally injected with LPS and survived for 1 week to demonstrate the changes of tyrosine hydroxylase（TH） expression and inflammatory factor release by Western blotting analysis. The other 5 monkeys were used for chronic experiment and 4 of them were intranigrally injected with LPS and survived for 24 weeks and 48 weeks respectively after the injection. Only one monkey was injected with saline as a control animal. The injections were stereotaxically made 3 times （ at weeks 0,8,16 respectively） in the substantia nigra on one side. The number of TH-positive neurons was detected by TH immunohistochemistry and the nigro-striatal levels of were determined by high pressure liquid chromatogram （HPLC）. Result In the acute experimental group of mokeys ： no obvious changes of TH expressing could be seen either on the injection side and control side, but it was shown the activation of microglia and increasing expression of HLA-DR TNF-α, IL-1β and COX-2 in the substantia nigra on injected side. In the chronic experimental group of mokeys, however, the number of TH-positive neurons in the injected substantia nigra and neurotransmitters levels in the nigro-striatal area were decreased. No obvious changes could be seen in the control case of saline iniected monkey. Conclusion LPS iniection in the substantia nigra of the primate causes severe inflammation in one week, which may lead to a long-term damage of dopaminergic neurons in a prolonged period.

关 键 词：脂多糖 黑质 炎性因子 神经递质 免疫组织化学 免疫印迹法 高压液相色谱法 恒河猴 

分 类 号：R742.5[医药卫生—神经病学与精神病学]