SO2和NO2混合气对大鼠呼吸系统的影响

目的探讨二氧化硫(SO2)和二氧化氮(NO2)混合气对大鼠呼吸系统的影响及损伤机制。方法40只成年大鼠随机分为4组，即1个对照组和3个染毒组，静式吸入染毒。3个染毒组sch和N02浓度分别为：低浓度组8，5mg／m^3：中浓度组16，10mg/m^3；高浓度组32，20mg／m^3，对照组吸入正常清洁空气。每天染毒2h，连续21d。乙醚麻醉下腹主动脉取血，做肺泡灌洗(BAL)，测定血清及肺泡灌洗液(BALF)中酸性磷酸酶(ACP)、碱性磷酸酶(AKP)、乳酸脱氢酶(LDH)、超氧化物歧化酶(SOD)、谷胱甘肽-S转移酶(GST)的活性及白蛋白、丙二醛(MDA)含量。结果染毒后大鼠血清和BALF中ACP、AKP活性增强；白蛋白、MDA含量增加；高浓度组BALF中SOD活性明显下降，与对照组比较有显著性差异。结论SO2和NO2混合气可引起肺上皮细胞通透性增加及肺组织氧化损伤。

Effect of mixtures of SO2 and NO2 on respiratory system in rats

Objective To explore the damage mechanism on respiratory s ystem in rats exposed to mixture of sulfur dioxide(SO 2)and nitrogen dioxide(NO 2).Methods 40 rats were randomly divided into 4 groups,i.e.a control group and 3 treated groups.Rats in control group were exposed to genera l air.Mixed gases of SO 2 and NO 2 were inhaled by static state in teated rats ,2?h per day for 21?d.Low,middle and high concentrations of SO 2 and NO 2 we re 8 and 5,16 and 10,32 and 20?mg/m3 respectively.After 3 weeks,the levels o f biochemical indexes and the activities of enzymes in serum and in bronchiolar l avage fluid (BALF) were measured.Results The atcivities of alkaline phosphatase (AKP) and acid phosphatase (ACP) in exposed groups were higher than that in control group (P<0.01) especially middle and high dosage groups;The levels of malondiadeh yde (MDA) and albumin in serum and BALF were increased in treated groups,especia lly in serum;superoxide dismutase (SOD) in BALF were decreased,there were statis tical difference between exposed groups and control group (P<0.05).Conclusion Mixtures of SO 2 and NO 2 may induce pulmona ry epithelial permeability increase and oxidant injury.