去铁胺与超氧阴离子反应的γ射线和脉冲辐解研究

Gamma and pulse radiolysis investigation of the reaction of desferrioxamine with superoxide anions.

作者信息

Sabourault D, Ribiere C, Nordmann R, Houee-Levin C, Ferradini C

机构信息

Department of Biomedical Research on Alcoholism, Faculté de Médecine, Université René Descartes, Paris, France.

出版信息

Int J Radiat Biol. 1989 Dec;56(6):911-21. doi: 10.1080/09553008914552381.

DOI:10.1080/09553008914552381

PMID:2574220

Abstract

The kinetic scheme of the reaction of desferrioxamine (DFO) with O2-. was studied using pulse and gamma-radiolysis. The rate constant k(O2-. + DFO) is equal to 1.3 +/- 0.1 x 10(6) dm3 mol-1s-1 at pH 7.4. Studying the competition between DFO and ferricytochrome-c for O2-. generated by gamma-radiolysis, we observed that the nitroxide free radical resulting from the reaction of O2-. with DFO and the product(s) resulting from the decay of this nitroxide radical act inversely towards the cytochrome-c-Fe3+/cytochrome-c-Fe2+ redox couple. This explains the discrepancy between our value of k(O2-. + DFO) and the one measured previously using ferricytochrome-c for the detection of O2-. The reported results show that DFO acts as a powerful O2-. scavenger, and that the products resulting from the reaction of DFO with O2-. can initiate oxidative and/or reductive reactions that should be taken into account in interpreting the effects of DFO in vitro and in vivo.

摘要

采用脉冲和γ辐解研究了去铁胺（DFO）与超氧阴离子（O₂⁻·）反应的动力学机制。在pH 7.4时，速率常数k（O₂⁻· + DFO）等于1.3±0.1×10⁶ dm³ mol⁻¹ s⁻¹。通过研究DFO与高铁细胞色素c对γ辐解产生的O₂⁻·的竞争，我们观察到O₂⁻·与DFO反应生成的氮氧自由基及其衰变产物对细胞色素c-Fe³⁺/细胞色素c-Fe²⁺氧化还原电对的作用相反。这解释了我们测得的k（O₂⁻· + DFO）值与先前使用高铁细胞色素c检测O₂⁻·时测得的值之间的差异。报道的结果表明，DFO是一种强大的O₂⁻·清除剂，并且DFO与O₂⁻·反应产生的产物可引发氧化和/或还原反应，在解释DFO在体外和体内的作用时应予以考虑。