THE REGULATION OF ENDOTHELIAL CONSTITUTIVE NITRIC OXIDE SYNTHASE IN REGENERATED ENDOTHLIAL CELLS

再生内皮细胞内皮组成型一氧化氮合酶的调节

基本信息

批准号：
08670802
负责人：
OHARA Yuichi
金额：
$ 1.6万
依托单位：
KYUSHU UNIVERSITY
依托单位国家：
日本
项目类别：
Grant-in-Aid for Scientific Research (C)
财政年份：
1996
资助国家：
日本
起止时间：
1996 至 1998
项目状态：
已结题

项目摘要

We tested the hypothesis that accelerated degradation of endothelium-derived nitric oxide by superoxide anion in regenerated endothelium after baloon denudation. To measure superoxide anion production within normal pig coronary arteries (control vessels) and coronary arteries two weeks after baloon dunudation (injured vessels), we used an assay for superoxide anion based on the chemiluminescence of lucigenin using luminometer (Shimazu). In pathological studies, moderate intimal thickening was observed in injured vessels. In separate isometric tension studies, serotonin- induced vasoconstriction was markedly augmented in injured vessel segments. Injured vessels produced two to threefold more superoxide anion than control vessels (n = 8). Interestingly, there was no difference between denuded control vessels and denuded injured vessels, suggesting that the regenerated endothlium is a source of superoxide anion production. To further investigate the molecular mechanisms of excess production of superoxide anion within regenerated endothlium, we excised injured coronary vessels and quantitated the expression of enzyme by immunohistochemical method using monoclonal antibody against mouse endothelial constitutive nitric oxide synthase (ecNOS), mouse Cu-Zn containing superoxide dismutase (Cu-Zn SOD), and mouse xanthine dehydrogenase (XDH). We observed ecNOS expression was significantly attenuated within regenerated endothlium, whereas either Cu-Zn SOD or XDH expression unchanged. Increased endothelial superoxide anion production and attenuated expression of ecNOS within regenerated endothlium after baloon denudation may play an important role in the early atherosclerotic process.

我们测试了这样的假设：球囊剥脱后再生内皮中的超氧阴离子加速了内皮源性一氧化氮的降解。为了测量正常猪冠状动脉（对照血管）和气球毁坏后两周的冠状动脉（受伤血管）内超氧阴离子的产生，我们使用光度计（Shimazu）基于光泽精的化学发光来测定超氧阴离子。在病理学研究中，在受损血管中观察到中度内膜增厚。在单独的等长张力研究中，受伤血管段中血清素诱导的血管收缩显着增强。受伤血管产生的超氧阴离子是对照血管的两到三倍（n = 8）。有趣的是，裸露的对照血管和裸露的受伤血管之间没有差异，这表明再生的内皮是超氧阴离子产生的来源。为了进一步研究再生内皮细胞中超氧阴离子过量产生的分子机制，我们切除了受损的冠状血管，并使用抗小鼠内皮组成型一氧化氮合酶（ecNOS）的单克隆抗体、含有超氧化物的小鼠铜锌，通过免疫组织化学方法定量了该酶的表达。歧化酶（Cu-Zn SOD）和小鼠黄嘌呤脱氢酶（XDH）。我们观察到再生内皮细胞内 ecNOS 表达显着减弱，而 Cu-Zn SOD 或 XDH 表达不变。球囊剥脱后内皮超氧阴离子产生增加和再生内皮内ecNOS表达减弱可能在早期动脉粥样硬化过程中发挥重要作用。