Superoxide dismutase and cytochrome oxidase in collapsed lungs: possible role in reexpansion edema.
Superoxide dismutase and cytochrome oxidase in collapsed lungs: possible role in reexpansion edema.
复制标题
塌陷肺中的超氧化物歧化酶和细胞色素氧化酶：在复张水肿中可能发挥作用。
DOI：
10.1152/jappl.1988.65.1.235
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发表时间：
1988
期刊：
影响因子：
--
通讯作者：
Fulmer,JD
中科院分区：
文献类型：
--
作者：
Jackson,RM;Brannen,AL;Veal,CF;Fulmer,JD
本研究探讨了肺塌陷对兔超氧化物歧化酶(SOD)、细胞色素氧化酶(Cytox)和丙酮酸激酶(PYKI)活性的影响。在塌陷和对侧肺中进行氰化物不敏感呼吸测量，作为细胞内自由基产生的指标。兔右肺衰竭7天后处死动物。用10(-5)M KCN(总SOD)和10(-3)M KCN(线粒体或MnSOD)分别测定对照兔肺中约25个SOD单位/mg DNA和11个SOD单位/mg DNA。右肺衰竭后7d线粒体超氧化物歧化酶活性下降25%(P<0.05)，而左、右肺总超氧化物歧化酶活性无明显变化。对照兔细胞色素C·min~(-1)、mgDNA~(-1)的平均活性约为0.009摩尔。右肺塌陷后7天，肺组织Cyt OX活性下降40%以上(P<0.05)，而对侧左肺肺组织Cyt OX活性无明显变化。组织缺氧引起的无氧糖酵解的标志--丙酮酸激酶活性，在塌陷的右肺增加了49%(P<0.01)。氰化物不敏感呼吸在塌陷7天的肺(2.28+/-0.66微升O2.min-1.g-1)比对侧肺(1.24+/-0.34，P<0.05)高83%，表明O2-增加。以及在常氧PO2(约150托)下匀浆后组织中H_2O_2的产生。
This study examined the effects of lung collapse, a condition that causes relative hypoxia in lung tissues, on superoxide dismutase (SOD), cytochrome oxidase (cyt ox), and pyruvate kinase (py ki) activities in rabbits. Cyanide-insensitive respiration measurements were done in collapsed and contralateral lungs, as an index of intracellular free radical production. Rabbits' right lungs were collapsed for 7 days after which the animals were killed. We found that control rabbit lungs contained approximately 25 SOD units/mg DNA measured with 10(-5) M KCN (total SOD) and approximately 11 SOD units/mg DNA measured with 10(-3) M KCN (mitochondrial or MnSOD). Right lung collapse caused a 25% decrease in mitochondrial SOD activity after 7 days (P less than 0.05), whereas no significant changes occurred in right or left lungs' total SOD activity. In control rabbits cyt ox activity averaged approximately 0.009 mumol ferrocytochrome c.min-1.mg DNA-1. Right lung collapse caused a greater than 40% decrease in cyt ox activity after 7 days of collapse (P less than 0.05), whereas cyt ox activity in contralateral left lungs did not change. Pyruvate kinase activity, a marker for anaerobic glycolysis resulting from tissue hypoxia, increased 49% in collapsed right lungs (P less than 0.01). Cyanide-insensitive respiration was 83% higher in 7 day-collapsed lungs (2.28 +/- 0.66 microliters O2.min-1.g-1) compared with contralateral lungs (1.24 +/- 0.34, P less than 0.05), indicating increased O2-. and H2O2 production in this tissue after homogenization at normoxic PO2 (approximately 150 Torr).(ABSTRACT TRUNCATED AT 250 WORDS)