长期香烟烟雾吸入对大鼠的慢性毒作用

目的探讨长期香烟烟雾吸入对大鼠的慢性毒性作用。方法健康雄性Wistar大鼠18只,随机分为正常对照组、低浓度（20%）染毒组和高浓度（60%）染毒组。染毒组大鼠整体暴露于动式气体染毒装置,烟雾吸入。染毒期间对大鼠定期进行体质量测量,在第5周、13周、21周、45周末染毒后分别收集各组大鼠24 h尿液进行8-羟基脱氧鸟苷（8-OHdG）测定,第45周末处死大鼠,观察肺脏病理改变与骨髓细胞微核率。结果肺脏病理切片显示染毒组大鼠肺气肿改变明显,支气管炎症反应逐渐加重。染毒组大鼠体质量增长均显著低于对照组;同时在各个时间点8-O-HdG水平明显升高,高浓度组升高更为显著;各染毒组微核率明显升高。上述变化均有统计学意义（P〈0.05）。结论长期香烟烟雾吸入对大鼠有慢性毒性作用。

Chronic Toxicity of Cigarette Smoke on Rats

Objective To study the chronic toxicity of tobacco smoke on rats exposed for a long time. Methods Wistar rats were divided into low, high concentration and control groups randomly, 6 for each. Animals in the exposed groups were set to gas inhalation chamber, 30 minutes each time and twice a day, 5 days a week, 45 weeks together. The rats were weighted regularly during the exposed pe- riod, A collection of 24 h urine was conducted for 8-OHdG detection at the fifth,thirteenth,twenty-first and forty-fifth week. When dissected at the end of 45 weeks,the rat lung tissue and thigh-bone were taken for pathological observation and micronucleus test. Results Emphysema pulmonum and bronchitis in lung tissue were observed in the exposed groups. Weight gain of the exposed rats was significantly slower than the control group. The 8-OHdG level in the rat urine significantly increased, especially in the high concentration group,so did the micronncleus rates. Conclusion Long time tobaco smoke may lead to convinced chronic toxicity on rats.