Poderoso J J, Fernandez S, Carreras M C, Tchercanski D, Acevedo C, Rubio M, Peralta J, Boveris A
Laboratory of Oxygen Metabolism, School of Medicine, University of Buenos Aires, Argentina.
Circ Shock. 1994 Dec;44(4):175-82.
Defective oxygen consumption and a pathological dependence of oxygen uptake on O2 supply have been considered important events in sepsis. To relate these features with tissue and mitochondrial metabolism, we studied oxygen uptake in whole isolated and perfused rat liver at two O2 supply levels, in the same liver slices, and in isolated liver mitochondria. Experimental sepsis in rats was induced by cecal ligation and double-gauge puncture. The results showed that liver and tissue slices from septic animals had a 60% greater O2 uptake than that of controls and that, during sepsis, liver O2 uptake was markedly dependent on O2 supply. Concomitantly, mitochondrial O2 uptake was nearly 30% greater with malate-glutamate as substrate, but not with succinate; lowering O2 concentration in the medium did not alter the enhanced function. In submitochondrial, only NADH-dehydrogenase activity was 100% higher in septic samples. At least, in some tissues, O2 dependence is a function of O2 availability, sensitized by increased mitochondrial O2 uptake related to changes in respiratory enzymes.
氧消耗缺陷以及氧摄取对氧供应的病理依赖性被认为是脓毒症中的重要事件。为了将这些特征与组织和线粒体代谢联系起来，我们在两个氧供应水平下，对完整的离体灌注大鼠肝脏、相同的肝切片以及离体肝线粒体中的氧摄取进行了研究。通过盲肠结扎和双套管穿刺诱导大鼠发生实验性脓毒症。结果表明，脓毒症动物的肝脏和组织切片的氧摄取比对照组高60%，并且在脓毒症期间，肝脏氧摄取明显依赖于氧供应。同时，以苹果酸 - 谷氨酸作为底物时，线粒体的氧摄取增加了近30%，但以琥珀酸作为底物时则没有增加；降低培养基中的氧浓度并没有改变增强的功能。在亚线粒体中，只有脓毒症样本中的NADH脱氢酶活性高出100%。至少在某些组织中，氧依赖性是氧可用性的函数，因与呼吸酶变化相关的线粒体氧摄取增加而变得敏感。
