SO_2污染对运动大鼠心肺组织的氧化损伤效应

Effect of Sulfur Dioxide Pollution on Oxidative Damage in Heart and Lungs of Exercised Rats

目的研究不同浓度SO2污染对运动大鼠心肺组织超氧化物歧化酶(SOD)活力、还原型谷胱甘肽(GSH)及丙二醛(MDA)含量的影响,探讨SO2污染对运动大鼠心肺组织损伤的机制。方法48只SD雄性大鼠随机分为8组:空白对照组(RG)、单纯运动组(EG)、低污染运动组(LEG)、低污染安静组(LRG)、中污染运动组(MEG)、中污染安静组(MRG)、高污染运动组(HEG)和高污染安静组(HRG)。除了RG和EG,其余各组均置于不同浓度SO2污染环境中(5mg/m3,10 mg/m3,15 mg/m3),运动组大鼠进行跑轮运动(8 m.min-1,2 h.d-1,共10 d)。24 h后处死大鼠,取心肺组织匀浆后立即进行抗氧化酶和脂质过氧化水平测定。结果肺组织SOD活力HEG、HRG、MEG、MRG、LEG较RG显著降低(P<0.05);心脏却出现EG、MRG升高而HRG、HEG下降的变化趋势(P<0.05)。心肺组织的GSH含量MRG升高而HEG、HRG、MEG下降(P<0.05)。MDA水平各实验组较安静对照组显著升高(P<0.05)。同一浓度污染环境中运动组与安静组相比,SOD活力、GSH含量显著降低,MDA水平显著升高(P<0.05),且存在剂量-效应关系。结论SO2污染可引起大鼠心肺组织的氧化损伤,而SO2污染对运动大鼠心肺组织的氧化损伤效应比安静组更明显。

Objective To investigate the effect of sulfur dioxide （SO2） pollution on activity of SOD, levels of GSH and MDA in heart and lungs of exercised rats, in order to elucidate the toxicological mechanism of SO2 pollution. Method 48 SD rats were randomly divided into eight groups： rest group （RG）, exercise group （EG）, low pollution exercise group （LEG） , low pollution rest group （LRG）, middle pollution exercise group （MEG）, middle pollution rest group （MRG）, high pollution exercise group （HEG） and high pollution rest group （HRG）. All groups, except RG and EG, were exposed to SO2 with different concentration （5 mg.m^3^- 1,10 mg.m^3^-1,15mg. m^3^-1）, meanwhile exercised rats were running in a motor- driven wheel at a speed of 8 m. min^-1, 2 h.d^- 1 for 10 days. Rats were killed at 24h after treatment and the anti - oxidative enzymes activity and lipid peroxidation （LPO） levels were measured. Results Compared with RG, SOD activity of lung tissues significantly decreased in HEG, MEG, LEG （ P 〈 0.05）, whereas the change of SOD activity of heart showed a tendency that EG, MRG raise and HRG, HEG decline（ P 〈 0.05）. GSH level of heart and lungs tissues appeared a conspicuous increase in MRG and a noticeable decrease in HEG, HRG, MEG（ P 〈 0.05）. MDA level of heart and lung tissues in each group had a significant increase in comparison with RG（ P 〈 0.05）. Comparing with rest group in the same polluted environment, SOD activity and GSH level of heart and lung tissues in exercise groups had a markedly decrease while MDA level significantly increased （ P 〈 0.05）, and there was a dose - response relationship. Conclusion SO2 pollution could induce oxidative damage of exercise rats＇ heart and lung tissues, which is more significant than rest rats.