Lee J S, Mustafa M G, Afifi A A
Department of Environmental Health Sciences, School of Public Health, University of California, Los Angeles 90024.
J Toxicol Environ Health. 1990;29(3):293-305. doi: 10.1080/15287399009531392.
To examine the pulmonary effects of relatively low levels of NO2 and O3, and test for any possible interaction in their effects, we exposed 3-mo-old male Sprague-Dawley rats, free of specific pathogens, to either filtered room air (control) or 1.20 ppm (2256 micrograms/m3) NO2, 0.30 ppm (588 micrograms/m3) O3, or a combination of the two oxidants continuously for 3 d. We studied a series of parameters in the lung, including lung weight, and enzyme activities related to NADPH generation, sulfhydryl metabolism, and cellular detoxification. The results showed that relative to control, exposure to NO2 caused small but nonsignificant changes in all the parameters; O3 caused significant increases in all the parameters except for superoxide dismutase; and a combination of NO2 and O3 caused increases in all the parameters, and the increases were greater than those caused by NO2 or O3 alone. Statistical analysis of the data showed that the effects of combined exposure were synergistic for 6-phosphogluconate dehydrogenase, isocitrate dehydrogenase, glutathione reductase, and superoxide dismutase activities, and additive for glutathione peroxidase and disulfide reductase activities, but indifferent from those of O3 exposure for other enzyme activities.
为了研究相对低浓度的二氧化氮（NO₂）和臭氧（O₃）对肺部的影响，并测试它们的影响中是否存在任何可能的相互作用，我们将3月龄无特定病原体的雄性斯普拉格-道利大鼠持续3天暴露于过滤后的室内空气（对照）或1.20 ppm（2256微克/立方米）的NO₂、0.30 ppm（588微克/立方米）的O₃或这两种氧化剂的组合环境中。我们研究了一系列肺部参数，包括肺重量以及与烟酰胺腺嘌呤二核苷酸磷酸（NADPH）生成、巯基代谢和细胞解毒相关的酶活性。结果表明，与对照组相比，暴露于NO₂会使所有参数发生微小但不显著的变化；O₃会使除超氧化物歧化酶外的所有参数显著增加；NO₂和O₃的组合会使所有参数增加，且增加幅度大于单独使用NO₂或O₃时。对数据的统计分析表明，联合暴露对6-磷酸葡萄糖酸脱氢酶、异柠檬酸脱氢酶、谷胱甘肽还原酶和超氧化物歧化酶活性的影响具有协同作用，对谷胱甘肽过氧化物酶和二硫键还原酶活性的影响具有相加作用，但对其他酶活性的影响与O₃暴露时无差异。
