Decomposition of N-nitrosamines, and concomitant release of nitric oxide by Fenton reagent under physiological conditions
Decomposition of N-nitrosamines, and concomitant release of nitric oxide by Fenton reagent under physiological conditions
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DOI：
10.1016/s1383-5718(02)00168-7
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发表时间：
2002-09-26
影响因子：
1.9
通讯作者：
Kikugawa, K
中科院分区：
文献类型：
--
作者：
Hiramoto, K;Ryuno, Y;Kikugawa, K
在磷酸盐缓冲液中，N-亚硝基二甲胺（NDMA）被H_2O_2和Fe（11）离子组成的芬顿试剂快速分解。电子自旋共振（ESR）研究表明，在NDMA和N-亚硝基二乙胺（NDEA）存在下，芬顿试剂与DMPO反应生成的DMPO-OH加合物的4条1：2：2：1特征ESR信号消失，表明N-亚硝胺与芬顿试剂发生了相互作用。用半胱氨酸-Fe（II）和N-甲基-D-葡糖胺二硫代氨基甲酸盐（MGD）-Fe（II）配合物通过ESR技术估计，用芬顿试剂处理N-亚硝胺产生一氧化氮（NO）。分别观察到2个半胱氨酸-Fe（II）-NO和2个半胱氨酸-Fe（II）-2 NO复合物的特征3和单线信号，以及MGD-Fe（II）-NO的三线信号。NO与水相溶解氧反应生成的最终氧化产物NO2-测定结果表明，NO的释放量相当大。只有在中性缓冲液中孵育时才能观察到少量的NO从N-亚硝胺中自发释放。上述结果表明，在与活性氧接触时，N-亚硝胺被分解并伴随着NO的释放。(C)2002 Elsevier Science B. V.保留所有权利。
N-Nitrosodimethylamine (NDMA) in phosphate buffer was rapidly decomposed by Fenton reagent composed of H2O2, and Fe(11) ion. Electron spin resonance (ESR) studies using 5,5-dimethyl-1-pyrroline N-oxide (DMPO) showed that characteristic four line 1:2:2:1 ESR signals due to the DMPO-OH adduct formed on treatment of DMPO with Fenton reagent disappeared in the presence of NDMA, and N-nitrosodiethylamine (NDEA), suggesting the interaction of the N-nitrosamines with Fenton reagent. Treatment of the N-nitrosamines with Fenton reagent generated nitric oxide (NO) as estimated by ESR technique using cysteine-Fe(II), and N-methyl-D-glucaminedithiocarbamate (MGD)-Fe(II) complexes. Characteristic 3, and single line signals due to 2 cysteine-Fe(II)-NO, and 2 cysteine-Fe(II)-2 NO complexes, respectively, and three line signals due to MGD-Fe(II)-NO were observed. Considerable amount of NO were liberated as determined by NO2-, the final oxidation product of NO formed by reaction with dissolved oxygen in the aqueous medium. Spontaneous release of a small amount of NO from the N-nitrosamines was observed only on incubation in neutral buffers. Above results indicate that the N-nitrosamines were decomposed accompanying concomitant release of NO on contact with reactive oxygen species. (C) 2002 Elsevier Science B.V. All rights reserved.