二苯基甲烷二异氰酸酯对小鼠3种器官的自由基损伤作用研究

A Study on free radical damage to three organs of mice by diphenylmethane diisocyanate

目的评价二苯基甲烷二异氰酸酯(MDI)对小鼠肺脏、睾丸、肝脏3种器官的自由基损伤作用及探讨其作用机制。方法采用静式吸入染毒,观察MDI对小鼠肺脏、睾丸、肝脏的超氧化物歧化酶(SOD)、丙二醛(MDA)、谷胱甘肽(GSH)和一氧化氮(NO)的影响。结果 MDI可引起3种靶器官中MDA、NO含量和诱导型NO合成酶(i-NOS)活力增加,GSH和SOD在3种靶器官中均有消耗,表明MDI可导致靶器官内氧自由基和NO自由基的增多。结论呼吸道暴露于MDI可引起多个靶器官的自由基损伤,主要表现为抗氧化物质的减少和自由基增多,同时激活i-NOS诱导NO水平升高,从而对组织产生损伤。接触MDI的劳动者应采取个人防护措施。

[ Objective] To evaluate the free radicals damage to lungs, testis and livers of mice caused by diphenylmethane diisocyanate（ MDI}, discuss its mechanism. [ Methods] Static type suction canister was used for mice to inhale MDI, the levels of superoxide dismutase （ SOD）, malondialdehyde （ MDA）, glutathione （ GSH ） and nitric oxide （ NO ） in 3 targeted tissues were determined in view of free radicals damage. [ Results] MDI exposure could increase the levels of MDA and NO, as well as the activity of inducible NO synthase { i-NOS） in 3 targeted tissues. GSH and SOD were all consumed in 3 targeted tissues. The results suggested that MDI could induce the oxygen free radicals and NO free radicals damage in targeted tissues. [ Conclusion ] MDI inhalation can cause free radicals damage to targeted tissues, which the main performances are the decrease of antioxidants and increase of free radicals. Meanwhile, MDI can activate i-NOS to induce the increase of NO level, which would cause tissue damage. Workers exposed to MDI should take personal protection measures.