汽油尾气致大鼠肺组织氧化损伤机制的研究  

Oxidative Damage of Gasoline Engine Exhausts to Rat Lung Tissues

作　　者：车望军[1,2] 王玲[1] 罗擎英[1] 吴媚[1] 张遵真[1] 

机构地区：[1]四川大学华西公共卫生学院环境卫生教研室,成都610041 [2]昆明市疾病预防控制中心

出　　处：《四川大学学报（医学版）》2009年第1期11-14,47,共5页Journal of Sichuan University(Medical Sciences)

基　　金：国家自然科学基金(批准号30571535)资助

摘　　要：目的探讨汽油尾气对大鼠肺DNA损伤、8-羟基鸟嘌呤DNA糖苷酶-1(OGG1)表达和细胞超微结构的影响。方法将汽油尾气的颗粒物、冷凝物和半挥发性有机物的二氯甲烷提取物以0、5.6、16.7和50.0L/kg的剂量经气管滴注染毒SD大鼠,每周一次,共4次,末次染毒24h后处死动物,用彗星实验检测肺组织细胞中DNA单链断裂水平,免疫组化检测肺组织中OGG1的含量,并在电镜下观察各型肺细胞超微结构的变化。结果在汽油尾气16.7和50.0L/kg组,肺组织细胞的拖尾率明显高于溶剂对照组(P<0.05),并有随剂量增加而增加的趋势,但各剂量组尾长的增加均无统计学意义;而汽油尾气中、高剂量组OGG1蛋白水平明显增加(P<0.05);在汽油尾气50.0L/kg组,肺组织各型细胞中的线粒体发生肿胀和空泡化,且线粒体数量明显减少。结论汽油尾气可诱导大鼠肺组织DNA单链断裂、OGG1蛋白含量增加和线粒体的损伤。Objective To study the effects of extracts of condensate, particulates and semivolatile organic compounds from gasoline engine exhaust on DNA damage, 8-oxoguanine DNA glycosylase-1 （OGG1） expression, and changes of ultra-structures in lungs of rats. Methods Organic extracts of gasoline engine exhaust （GEE） was intratrachealy instilled into rat lungs at 0, 5.6, 16.7, and 50.0 L/kg body weight, respectively, once a week for a month. The single DNA strand break was measured by comet assay. The OGG1 was determined using immunohistochemistry method. The ultrastructure of lung cells was observed with electronic microscope. Results The rates of tailed cells detected by the comet assay increased significantly when the rats were exposed to 16.7 and 50.0 L/kg of GEE compared with those exposed to solvent only （P〈0.05）. However, the tail length did not differ significantly between the groups. Similarly, exposure to 16.7 and 50.0 L/kg of GEE led to increased OGG1 significantly. Significant changes of mitoehondria in type Ⅰ and Ⅱ alveolar cells as well as respiratory bronchiole epithelial cells were observed, which included decrease of numbers, pyknosis and swelling. Conclusion Gasoline engine exhausts induce single DNA strand break, increase OGG1 expression, decrease numbers of mitochondria, and destroy ultrastructures of mitochondria in various lung cells of rats.

关 键 词：汽油尾气 DNA损伤 线粒体 8-羟基鸟嘌呤DNA糖苷酶1 肺 

分 类 号：R114[医药卫生—卫生毒理学]