Microvascular oxidative stress preceding leukocyte activation elicited by in vivo nitric oxide suppression.
Microvascular oxidative stress preceding leukocyte activation elicited by in vivo nitric oxide suppression.
复制标题
体内一氧化氮抑制引起白细胞活化之前的微血管氧化应激。
DOI：
10.1152/ajpheart.1994.266.6.h2410
复制
发表时间：
1994
期刊：
影响因子：
--
通讯作者：
Schmid-Schonbein,GW
中科院分区：
文献类型：
--
作者：
Suematsu,M;Tamatani,T;Delano,FA;Miyasaka,M;Forrest,M;Suzuki,H;Schmid-Schonbein,GW
本研究旨在探讨体内内源性一氧化氮抑制促进白细胞黏附的机制。用NG-硝基-L-精氨酸甲酯(L-NAME，100微米)灌流大鼠肠系膜微循环，用数字显微荧光摄影技术观察微循环中动脉、静脉内皮细胞和肥大细胞内氧化剂的形成。同时测定贴壁白细胞密度。L-NAME诱导的小动脉、小静脉内皮细胞和肥大细胞CDCFs的荧光强度随时间的延长而显着增加，随后出现白细胞的牢固黏附。与N-甲酰-甲硫基-亮氨酰苯丙氨酸诱导的CDCF值升高相比，L-NAME诱导的CDCF值升高呈现不同的空间分布，只有局部有白细胞黏附的静脉段CDCF值有荧光增强。L-NAME灌流60min引起的小动脉和小静脉中过氧化氢的形成水平相当于880微米叔丁基氢过氧化氢灌流10min所引起的水平。用抗细胞间黏附分子-1、抗P-选择素或抗CD18McAb可在不取消CDCFs原位荧光的情况下减弱L诱导的小静脉白细胞黏附。去铁胺(50 mg/kg iv；L灌流前1h)可显著减少小动脉和小静脉铁催化的过氧化氢生成，但对间质肥大细胞的铁催化过氧化氢生成及随后的白细胞黏附无明显影响。这些结果表明，内源性一氧化氮可能调节肥大细胞、小动脉和小静脉微血管内皮细胞的氧化应激，从而在小静脉内白细胞的募集中发挥关键作用。
This study was aimed to determine the mechanism by which endogenous nitric oxide suppression promotes leukocyte adhesion in vivo. The rat mesenteric microcirculation was superfused with NG-nitro-L-arginine methyl ester (L-NAME; 100 microM), and intracellular oxidant formation in several microcirculatory cellular components such as arteriolar and venular endothelium and mast cells was visually monitored by digital microfluorography assisted by carboxydichlorofluorescein (CDCF), a hydroperoxide-sensitive fluorogenic probe. Adherent leukocyte density was measured simultaneously. L-NAME induced a significant time-dependent increase in CDCF fluorescence in arteriolar and venular endothelium and mast cells followed by firm adhesion of leukocytes. L-NAME-induced CDCF elevation showed a different spatial distribution compared with that evoked by N-formylmethionyl-leucyl-phenylalanine, in which only local venular segments with adhering leukocytes exhibited CDCF fluorescence enhancement. The level of hydroperoxide formation in arterioles and venules evoked by 60-min L-NAME superfusion was equivalent to that induced by the superfusion of approximately 880 microM tert-butyl hydroperoxide for 10 min. Pretreatment with anti-intracellular adhesion molecule-1, anti-P-selectin, or anti-CD18 monoclonal antibody attenuated L-NAME-elicited venular leukocyte adhesion without abolishing CDCF fluorescence in situ. Pretreatment with desferioxamine (50 mg/kg iv; 1 h before L-NAME superfusion) significantly diminished the iron-catalyzed hydroperoxide formation in arterioles and venules, but not in interstitial mast cells, as well as subsequent venular leukocyte adhesion. These findings indicate that endogenous nitric oxide may modulate oxidative stress in mast cells, arteriolar and venular microvascular endothelium and thereby can play a crucial role in leukocyte recruitment in venules.