中文摘要：

目的研究城市道路周边大气PM1.0对大鼠脑皮层组织及氧化应激水平的影响。方法将50只健康雄性SD大鼠随机分为5组,每组10只,分别为空白对照组、生理盐水组和低（1.5 mg/kg）、中（7.5 mg/kg）、高（37.5 mg/kg）剂量PM1.0染毒组。乙醚麻醉后,采用气管滴注法进行染毒,隔天染毒1次,共染毒3次。于末次染毒7 d后,每组动物取脑皮层组织进行观察,并测定大鼠脑皮层中总超氧化物歧化酶（T-SOD）、谷胱甘肽过氧化物酶（GSH-Px）活力和丙二醛（MDA）含量及总抗氧化能力（T-AOC）。结果各染毒组大鼠脑皮层组织出现不同程度的病理改变,可见细胞排列紊乱、神经元数量减少、核固缩、染色质溶解等现象;且随着染毒剂量的升高,病理改变更为严重。与生理盐水组比较,中、高剂量PM1.0染毒组大鼠脑皮层T-SOD活力下降,MDA含量升高,T-AOC活力下降,差异均有统计学意义（P〈0.05）;各剂量染毒组大鼠脑皮层GSH-Px活力无明显变化（P〉0.05）。结论在本试验条件下PM1.0染毒可引起大鼠脑皮层组织结构出现病理性变化,其损伤可能与脑内氧化应激反应增加有关。

英文摘要：

Objective To study the effects of fine particulate matter（PM1.0） surrounding urban road on the cerebral cortex and its oxidative stress level in rats. Methods A total of 50 SD rats were randomly divided into five groups： control group, saline group and low（1.5 mg/kg body weight）, moderate（7.5 mg/kg body weight） and high（37.5 mg/kg body weight） dose group. The rats were anesthetized by ethyl ether, intratracheal instillation was used to expose PM1.0 suspension, once every other day, for3 times. Seven days later, the samples of cerebral cortex of every group were collected for pathological examination and determination of T-SOD, GSH-Px, T-AOC and MDA. Results The cerebral cortex tissues in moderate and high dose groups showed pathological changes, such as disorderly arranged cells, reduced cell number, karyopyknosis, chromatinolysis, and so on. Compared with the saline group, level of T-SOD and T-AOC in moderate group and high dose groups decreased significantly（P〈0.05）, the level of MDA in moderate group and high dose groups increased significantly（P〈0.05）. Conclusion Under the condition of this experiment, PM1.0 may cause tissue damage in cerebral cortex of rats, which may be associated with intensive oxidative stress.