Interference of carboxy-PTIO with nitric oxide- and peroxynitrite-mediated reactions
Interference of carboxy-PTIO with nitric oxide- and peroxynitrite-mediated reactions
复制标题
DOI：
10.1016/s0891-5849(96)00407-8
复制
发表时间：
1997-01-01
影响因子：
7.4
通讯作者：
Mayer, B
中科院分区：
文献类型：
--
作者：
Pfeiffer, S;Leopold, E;Mayer, B
羧基PTIO与NO快速反应产生NO2，并已被用作清除剂来测试一氧化氮（NO）在各种生理条件下的重要性。本研究探讨了羧基PTIO对几个NO和过氧亚硝酸盐介导的反应的影响。清除剂有效地抑制NO诱导的cGMP在内皮细胞中的积累，但增强了推定的过氧亚硝酸盐供体SIN-1的效果。羧基-PTIO完全抑制过氧亚硝酸盐诱导的游离酪氨酸形成3-硝基酪氨酸（EC（50）= 36 +/- 5 μ M）以及牛血清白蛋白的硝化。过氧亚硝酸盐介导的GSH亚硝化被药物刺激，EC（50）为0.12 +/- 0.03 mM，而由NO供体DEA/NO（0.1 mM）诱导的S亚硝化被清除剂抑制，IC 50为0.11 +/- 0.03 mM。用羧基-PTIO氧化NO导致形成亚硝酸盐，而不伴随产生硝酸盐。我们的研究结果表明，羧基PTIO的影响是多样的，并质疑其声称的特异性作为NO清除剂。版权所有（C）1997 Elsevier Science Inc.
Carboxy-PTIO reacts rapidly with NO to yield NO2 and has been used as a scavenger to test the importance of nitric oxide (NO) in various physiological conditions. This study investigated the effects of carboxy-PTIO on several NO- and peroxynitrite-mediated reactions. The scavenger potently inhibited NO-induced accumulation of cGMP in endothelial cells but potentiated the effect of the putative peroxynitrite donor SIN-1. Carboxy-PTIO completely inhibited peroxynitrite-induced formation of 3-nitrotyrosine from free tyrosine (EC(50) = 36 +/- 5 mu M) as well as nitration of bovine serum albumin. Peroxynitrite-mediated nitrosation of GSH was stimulated by the drug with an EC(50) of 0.12 +/- 0.03 mM, whereas S nitrosation induced by the NO donor DEA/NO (0.1 mM) was inhibited by the scavenger with an IC50 of 0.11 +/- 0.03 mM. Oxidation of NO with carboxy-PTIO resulted in formation of nitrite without concomitant production of nitrate. Our results demonstrate that the effects of carboxy-PTIO are diverse and question its claimed specificity as NO scavenger. Copyright (C) 1997 by Elsevier Science Inc.