Direct detection of reactive nitrogen species in experimental autoimmune uveitis.
Direct detection of reactive nitrogen species in experimental autoimmune uveitis.
复制标题
在实验性自身免疫性葡萄膜炎中直接检测反应性氮种。
DOI：
10.3341/kjo.2007.21.1.21
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发表时间：
2007-03
影响因子：
--
通讯作者：
Rao NA
中科院分区：
文献类型：
--
作者：
Bae SR;Wu GS;Sevanian A;Schultz BE;Zamir E;Rao NA
利用n -甲基- d -氨基葡萄糖二硫代氨基甲酸亚铁络合物（MGD）2-Fe2+作为自旋陷阱，通过电子自旋共振光谱（ESR）明确证明实验性自身免疫性葡萄膜视网膜炎中一氧化氮的产生。在Lewis大鼠中诱导实验性自身免疫性葡萄膜炎，在眼内炎症的高峰期，动物接受玻璃体内自旋诱捕器注射。从去核球上剥离的视网膜和脉络膜进行ESR。同样地，在实验性自身免疫性葡萄膜视网膜炎（EAU）高峰时获得的视网膜和脉络膜放置在含有luminal的小瓶中，并在Packard液体闪烁分析仪上计数化学发光。得到的ESR三线谱（g=2.04; aN=12.5 g）是加合物[(MGD)2-Fe2+-NO]的特征谱。该信号的大部分被诱导型一氧化氮合酶（iNOS）特异性抑制剂氨基胍消除，注射炎症视网膜与非炎症对照组相比检测到。在发炎的视网膜中加入碳酸氢盐，化学发光活性进一步增加了两倍；这种现象只能归因于高稳态过氧亚硝酸盐浓度的存在。研究表明，在EAU视网膜和脉络膜和生成过氧亚硝酸盐一氧化氮的明确存在。在发炎的视网膜和脉络膜中产生的这些高水平的活性氮肯定会导致不可逆的组织损伤，特别是在感光器等敏感部位。
Demonstrate unequivocally the generation of nitric oxide in experimental autoimmune uveoretinitis by electron spin resonance spectroscopy (ESR) using ferrous iron complex of N-methyl-D-glucamine dithiocarbamate, (MGD)2-Fe2+, as a spin trap. Experimental autoimmune uveitis was induced in Lewis rats, and at the peak of the intraocular inflammation, the animals received intravitreous injections of the spin trap. The retina and choroid dissected from the enucleated globes were subjected to ESR. Similarly, the retina and choroid obtained at the peak of experimental autoimmune uveo-retinitis (EAU) were placed in a vial containing luminal, and chemiluminescence was counted on a Packard liquid scintillation analyzer. The ESR three-line spectrum (g=2.04; aN=12.5 G) obtained was characteristic of the adduct [(MGD)2-Fe2+-NO]. The majority of this signal was eliminated by the inducible nitric oxide synthase (iNOS) specific inhibitor aminoguanidine injected inflamed retina was detected when compared with that of the non inflamed controls. The chemiluminescent activity was further increased two-fold by the addition of bicarbonate to the inflamed retina; the phenomenon is attributable only to the presence of a high steady-state concentration of peroxynitrite. The study shows an unequivocal presence of nitric oxide in EAU retina and choroid and the generation of peroxynitrite. High levels of these reactive nitrogen species generated in the inflamed retina and choroids are certain to cause irreversible tissue damage, especially at the susceptible sites such as photoreceptors.