de Castro R, Hughes M G, Xu G-Y, Clifton C, Calingasan N Y, Gelman B B, McAdoo D J
Department of Neuroscience and Cell Biology and Department of Human Biological Chemistry and Genetics, University of Texas Medical Branch, Galveston, TX 77555-1043, USA.
Exp Neurol. 2004 Dec;190(2):414-24. doi: 10.1016/j.expneurol.2004.05.046.
The release of reactive oxygen species (ROS) by neutrophils, which infiltrate the region of damage following spinal cord injury (SCI), was investigated to determine if such release is significant following spinal cord injury. The relationship of extracellular levels of hydroxyl radicals and hydrogen peroxide obtained by microdialysis sampling and oxidized protein levels in tissue to neutrophil infiltration following spinal cord injury was examined. Neither of the reactive oxygen species were elevated in the site of spinal cord injury relative to their concentrations in normal tissue at a time (24 h) when the numbers of neutrophils were maximum in the site of injury. Surprisingly, ablation with a neutrophil antiserum actually increased the level of oxidized proteins in Western blots. Thus, our findings are (1) that neutrophils, which infiltrate the site of damage following a spinal cord injury, do not release detectable quantities of reactive oxygen species; and (2) that the presence of neutrophils reduces the concentrations of oxidized proteins in the site of spinal cord injury. Therefore, release of reactive oxygen species by neutrophils does not contribute significantly to secondary damage following spinal cord injury. Reduced levels of oxidized proteins in the presence of neutrophils may reflect removal of damaged tissue by neutrophils.
研究了脊髓损伤（SCI）后浸润损伤区域的中性粒细胞释放活性氧（ROS）的情况，以确定脊髓损伤后这种释放是否显著。通过微透析采样获得的细胞外羟基自由基和过氧化氢水平与脊髓损伤后组织中氧化蛋白水平和中性粒细胞浸润之间的关系进行了研究。在损伤部位中性粒细胞数量最多的时间点（24小时），相对于正常组织中的浓度，脊髓损伤部位的两种活性氧均未升高。令人惊讶的是，用中性粒细胞抗血清消融实际上增加了蛋白质免疫印迹中氧化蛋白的水平。因此，我们的发现是：（1）脊髓损伤后浸润损伤部位的中性粒细胞不会释放可检测量的活性氧；（2）中性粒细胞的存在降低了脊髓损伤部位氧化蛋白的浓度。因此，中性粒细胞释放活性氧对脊髓损伤后的继发性损伤贡献不大。中性粒细胞存在时氧化蛋白水平降低可能反映了中性粒细胞对受损组织的清除。
