温石棉及3种代用纤维对Wistar大鼠氧化损伤作用的对比研究

Comparative research of oxidative damage of Wistar rats by chrysotile and three alternative fibers

目的对比研究温石棉及3种代用纤维对Wistar大鼠氧化损伤作用程度。方法测试分析温石棉及3种代用纤维(玻璃纤维、陶瓷纤维和岩棉纤维)的主要化学组分和粒径;分别使用温石棉及代用纤维悬液采用非暴露式气管滴注法对雄性Wistar大鼠进行染毒,染毒1、3和6个月后处死大鼠,称其体质量、肺质量,测定肺组织和血清中活性氧(reactive oxygen species,ROS)、丙二醛(malondiadehyde,MDA)含量及超氧化物歧化酶(superoxide dismutase,SOD)活力。结果温石棉及代用纤维的平均粒径<10μm,主要化学组分是SiO2,并含有少量的CaO,MgO和Al2O3。随着温石棉及代用纤维染毒Wistar大鼠时间的延长,大鼠体质量增长缓慢,肺质量高于阴性对照组(P<0.05);从染毒3个月开始,温石棉组、陶瓷纤维组和玻璃纤维组大鼠肺组织和血清中ROS、MDA含量均增高,岩棉纤维组从染毒6个月才升高(P<0.05),各组的ROS和MDA的含量:温石棉>陶瓷/玻璃>岩棉。从染毒1个月开始,温石棉组、陶瓷纤维组和玻璃纤维组肺组织和血清中SOD活性降低,岩棉纤维组从染毒6个月出现降低,差异具有统计学意义(P<0.05),各组SOD的活性:温石棉>陶瓷/玻璃>岩棉。结论温石棉及代用纤维均可导致Wistar大鼠氧化损伤,其氧化损伤程度:温石棉>陶瓷/玻璃>岩棉。

Objective To compare the oxidative damage of chrysotile asbestos and three substituted fibers in Wistar rats. Methods The main chemical composition and particle size of chrysotile asbestos and three kinds of substitute fibers(glass fibers, ceramic fibers and rock wool fibers) were tested and analyzed. Male Wistar rats were poisoned with chrysotile asbestos and alternative fibre suspension respectively by non-exposed tracheal drip. After 1, 3 and 6 months of exposure, the rats were executed and their body mass and lung mass were weighed. The contents of reactive oxygen species(ROS), malondiadehyde(MDA) and the activity of superoxide dismutase(SOD) in lung homogenate and serum were determined. Results The result showed that the average particle size of chrysotile asbestos and its substitute fibers is less than 10 μm. The main chemical component is SiO2, which contains a small amount of CaO, MgO and Al2O3. With the prolongation of exposure time to chrysotile asbestos and substitute fibers, the body weight of wistar rats increased slowly, and the lung mass of Wistar rats was higher than that of negative control group(P<0.05). From three months after exposure, the contents of ROS and MDA in lung tissue and serum of chrysotile group, ceramic fiber group and glass fiber group increased, while the contents of ROS and MDA in rock wool group increased from six months after exposure(P<0.05). The contents of ROS and MDA in each group were chrysotile asbestos>ceramic/glass>rock wool. The SOD activity in lung tissue and serum of chrysotile asbestos group, ceramic fiber group and glass fiber group decreased from one month to six months(P<0.05). The SOD activity in each group was chrysotile asbestos>ceramic/glass>rock asbestos. Conclusion Chrysotile asbestos and alternative fibers caused oxidative damage in Wistar rats. The degree of oxidative damage was chrysotile asbestos>ceramics/glass>rock wool.