Bound NO in human red blood cells: fact or artifact?
Bound NO in human red blood cells: fact or artifact?
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DOI：
10.1016/j.niox.2004.04.008
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发表时间：
2004-06-01
影响因子：
3.9
通讯作者：
Feelisch, M
中科院分区：
文献类型：
--
作者：
Bryan, NS;Rassaf, T;Feelisch, M
关于一氧化氮 (NO) 和红细胞 (RBC) 之间相互作用的性质和化学性质，特别是血红蛋白是否消耗或保留 NO 生物活性，存在相当大的争论。鉴于文献中报道的人类红细胞亚硝化水平范围广泛，我们试图研究是否存在一个共同点可以解释不同方法和反应条件之间的这种差异，以及生理学中是否可能存在这样的途径。在这里，我们发现人类和大鼠血红蛋白对 NO 的反应性存在显着差异，这为为什么灵长类动物红细胞中 NO 加合物的基础水平显着低于啮齿类动物提供了机制解释。我们进一步证明，无意中引入痕量亚硝酸盐和不完全的硫醇烷基化会导致血红素和硫醇亚硝基（基）化，并产生亚硝酰血红蛋白（NOHb）和S-亚硝基血红蛋白（SNOHb），而在生理亚硝酸盐浓度下，这两种物质在人红细胞中均检测不到。因此，在解释 SNOHb/NOHb 水平的实验结果时应谨慎行事，这些结果是在不了解亚硝酸盐污染程度的情况下获得的，特别是当涉及此类物种的生理作用时。 (C) 2004 Elsevier Inc. 保留所有权利。
There has been considerable debate over the nature and chemistry of the interaction between nitric oxide (NO) and red blood cells (RBCs), in particular whether hemoglobin consumes or conserves NO bioactivity. Given the vast range of nitrosation levels reported for human RBCs in the literature, we sought to investigate whether there was a common denominator that could account for such discrepancies across different methodologies and reaction conditions and if such a pathway may exist in physiology. Here, we show that there are marked differences in reactivity toward NO between human and rat hemoglobin, which offers a mechanistic explanation for why basal levels of NO-adducts in primate RBCs are considerably lower than those in rodents. We further demonstrate that the inadvertent introduction of trace amounts of nitrite and incomplete thiol alkylation lead to rapid heme and thiol nitros(yl)ation, with generation of nitrosylhemoglobin (NOHb) and S-nitrosohemoglobin (SNOHb), while neither species is detectable in human RBCs at physiological nitrite concentrations. Thus, caution should be exercised in interpreting experimental results on SNOHb/NOHb levels that were obtained in the absence of knowledge about the degree of nitrite contamination, in particular when a physiological role for such species is implicated. (C) 2004 Elsevier Inc. All rights reserved.