Azide투여가 고농도산소 노출에 의한 마우스 간내 반응성 산소의 발생과 제거에 미치는 영향

Abstract

An increased production of reactive oxygen species has been postulated as a major pathogenic factor of the tissue demage occurring in high oxygen environment. Azide could enhance the oxygen toxicity by inhibiting superoxide dismutase and catalase, enzymes which remove reactive oxygen species. Mice were treated intraperitoneally with azideI8.1㎎/㎏ body weight), and placed in a chamber saturated with 100 % O_2 for 3, 6, 12, 24, 48 or 72 h. Superoxide radical generation, and activities of xanthine oxidase, superoxide dismutase and catalase in homogenate of the mouse liver were measured. At 3 h of the treatment with azide/100 % O_2, superoxide radical generation was enhanced to more than 12 times of the control. Such increment was much higher in the liver of mice treated with both azide and 100 % O_2 than in that with either azide or 100 % O_2 alone. On the other hand, the activities of mitochondrial Mn-superoxide dismutase and catalase were decreased, while Cu, Zn-superoxide dismutase activity was elevated by the azide/oxygen treatment. Xanthine oxidase activity was markedly increased by the azide/oxygen treatment. These results indicate that superoxide radical generation in the mouse liver by the azide/oxygen treatment may be due to the inhibiton of Mn-superoxide dismutase and catalase, and due to increased xanthine oxidase activity. Treatment with azide alone did not decrease the activities of Mn-superoxide dismutase and catalase. This result suggested that azide did not effectively inhibit these enzymes in vivo.