百草枯对小鼠黑质纹状体多巴胺能系统的影响

目的 探讨百草枯对小鼠黑质纹状体通路的影响。方法 将39只新生C57BL小鼠随机分为5组，分别于出生后第10、11天每天喂食单剂量MPTP、百草枯和生理盐水。（1）MPTP0.3mg/kg组,n=8；（2）MPTP20mg/kg组，n=8；（3）百草枯0.07mg/kg组，n=8；（4）百草枯0.36mg/kg组，n=8；（5）等量生理盐水/kg组，n=7。正常饲养至4月龄观察小鼠自发性行为的变化，采用HPLC测定各组小鼠纹状体中多巴胺（DA）、5-羟色胺（5-HT）及其代谢产物含量，免疫组化方法检测中脑黑质细胞数量的变化。结果 MPTP20mg/kg组及百草枯0.36mg/kg组C57BL小鼠的自发性活动减少，纹状体中DA及其代谢产物含量降低，中脑黑质细胞数量减少。结论 新生期的C57BL小鼠暴露于大剂量的百草枯可产生类似于帕金森病（PD）的行为，黑质纹状体也发生相应的生化病理改变。

Influence of Paraquat onthe System of Substantial Nigra and Striatum in C57BL Mice

Purpose To investigate the influence of paraquat on substantial nigra and dopamine levels of striatum in C57BL mice. Methods 39 neonatal C57BL mice were randomly divided into 5 groups and were given paraquat or 1 methyl 4 phenyl 1,2,3,6 tetra hydropyridine(MPTP) orally in 10 th and 11 th days odl;(1) MPTP 0.3 mg/kg, n=8 ;(2) MPTP 20 mg/kg, n=8 ;(3) paraquat 0.07 mg/kg, n=8 ;(4) paraquat 0.36 mg/kg, n=8 ;(5) normal saline, n=7 .Adult spontaneous motor activity was observed at ages of 120 days,then the mice were decapitated and the contents of dopamine(DA),serotonin(5?HT),and their metabolites in striatum were analyzed.Meanwhile,the dopamine neuons at the mesencephalon were observed by the method of ABC immunohistochemistry. Results Mice given Paraquat 0.36 mg/kg and MPTP 20 mg/kg showed a marked bypoactive behavior and reduced the striatal contents of DA and metabolites without affecting 5?HT.Immunohistochemical staining showed that the amount of dopamine neurons at the midbrain decreased. Conclusions C57BL mice exposed to great amount of paraquat during the neonatal period could yield the alterations of behavior and some pathological and biochemical changes similar to parkinson disease.