Kooy N W, Lewis S J, Royall J A, Ye Y Z, Kelly D R, Beckman J S
Department of Pediatrics, University of Iowa, Iowa City 52242, USA.
Crit Care Med. 1997 May;25(5):812-9. doi: 10.1097/00003246-199705000-00017.
Production of nitric oxide via the cytokine-mediated activation of myocardial inducible nitric oxide synthase decreases myocardial contractility. Whether myocardial dysfunction is mediated directly by nitric oxide or indirectly through the formation of secondary reaction products, such as peroxynitrite, has not been established. Peroxynitrite, but not nitric oxide, reacts with the phenolic ring of tyrosine to form the stable product 3-nitro-L-tyrosine. Demonstration of tissue nitrotyrosine residues, therefore, infers the presence of peroxynitrite or related nitrogen-centered oxidants.
Retrospective analysis of human autopsy specimens.
University pathology and basic science laboratories.
Formalin-fixed, paraffin-embedded myocardial tissue samples were obtained from 11 patients with a diagnosis of sepsis, seven patients with a diagnosis of viral myocarditis, and five control patients without clinical or pathologic cardiac disease.
None.
Specific antibodies to nitrotyrosine were utilized to detect nitrotyrosine residues in human autopsy specimens. Cardiac tissue obtained from patients with myocarditis or sepsis demonstrated intense nitrotyrosine immunoreactivity in the endocardium, myocardium, and coronary vascular endothelium and smooth muscle. In contrast, connective tissue elements were without appreciable immunohistochemical staining. Nitrotyrosine antibody binding was blocked by coincubation with nitrotyrosine or nitrated bovine serum albumin, but not by aminotyrosine, phosphotyrosine, or bovine serum albumin. In situ reduction of tissue nitrotyrosine to aminotyrosine by sodium hydrosulfite also blocked antibody binding. Densitometric analysis of nitrotyrosine immunoreactivity demonstrated significantly higher values for specimens from myocarditis and sepsis patients when compared with control tissue specimens.
These results demonstrate the formation of peroxynitrite within the myocardium during inflammatory disease states, suggesting a role for peroxynitrite in inflammation-associated myocardial dysfunction.
细胞因子介导的心肌诱导型一氧化氮合酶激活所产生的一氧化氮会降低心肌收缩力。心肌功能障碍是由一氧化氮直接介导还是通过过氧化亚硝酸盐等二级反应产物的形成间接介导，目前尚未明确。过氧化亚硝酸盐而非一氧化氮会与酪氨酸的酚环反应形成稳定产物3-硝基-L-酪氨酸。因此，组织中硝基酪氨酸残基的存在意味着过氧化亚硝酸盐或相关氮中心氧化剂的存在。
对人体尸检标本进行回顾性分析。
大学病理和基础科学实验室。
从11例脓毒症诊断患者、7例病毒性心肌炎诊断患者和5例无临床或病理心脏疾病的对照患者中获取福尔马林固定、石蜡包埋的心肌组织样本。
无。
使用硝基酪氨酸特异性抗体检测人体尸检标本中的硝基酪氨酸残基。心肌炎或脓毒症患者的心脏组织在内膜、心肌以及冠状血管内皮和平滑肌中显示出强烈的硝基酪氨酸免疫反应性。相比之下，结缔组织成分没有明显的免疫组化染色。硝基酪氨酸抗体结合可通过与硝基酪氨酸或硝化牛血清白蛋白共同孵育而被阻断，但不能被氨基酪氨酸、磷酸酪氨酸或牛血清白蛋白阻断。用亚硫酸氢钠将组织中的硝基酪氨酸原位还原为氨基酪氨酸也可阻断抗体结合。对硝基酪氨酸免疫反应性的光密度分析表明，与对照组织标本相比，心肌炎和脓毒症患者标本的值显著更高。
这些结果表明在炎症性疾病状态下心肌内会形成过氧化亚硝酸盐，提示过氧化亚硝酸盐在炎症相关心肌功能障碍中起作用。
