NF-κB和MIP-1与多形核白细胞在大鼠脑缺血再灌注损伤中的作用

NF-κB, MIP-1 and polymorphonuclear cell infiltration following focal cerebral ischemia-reperfusion injury in rats

目的 :探讨在大鼠脑缺血再灌注损伤模型中NF κB、MIP 1的变化与多形核白细胞 (PMNs或PMNLs)浸润的关系 .方法 :SD大鼠 84只 ,随机分为对照组 (1 2只 ) ,假手术组(1 2只 ) ,实验组 (包括I/R 1h组、I/R 3h组、I/R 6h组、I/R 1 2h组和I/R 2 4h组 ,每组 1 2只 ) .在相应时间点处死大鼠后 ,取脑 .用ELISA法测定脑组织匀浆中MIP 1的浓度 ;用免疫组化方法检测NF κB和MPO的着色情况 ,并应用计算机图像分析系统进行灰度分析 .结果 :NF κB在再灌注后 1h表达升高 ,3h达高峰 ,2 4h仍处较高水平 ;大鼠脑组织MIP 1表达再灌注后于 1h开始升高 ,1 2h达高峰 ,2 4h有所下降 ,但仍处于较高水平 ,MPO于再灌注 6h开始升高 ,2 4h达高峰 .结论 :NF κB可能通过促进MIP 1表达 。

AIM: To investigate the relationship of the expressions of nuclear factor kappa B (NF κB) and macrophage inflammatory protein 1 (MIP 1) with the extent of polymorphonuclear cells (PMNs) infiltration after focal cerebral ischemia reperfusion injury in rats. METHODS: Eighty four SD rats were divided into control group ( n =12), sham operation group( n =12) and operation groups (I/R 1 h group, I/R 3 h group, I/R 6 h group, I/R 12 h group, I/R 24 h group, with 12 in each group). MIP 1 in cerebral homogenates was examined by ELISA, and NF κB and myeloperoxidase (MPO) were examined by immunohistochemical method. RESULTS: The expression of NF κB rose at 1 h after reperfusion, peaked at 3 h, and kept at high level at 24 h. The expression of MIP 1 rose at 1 h after reperfusion, peaked at 12 h ( P <0.05 compared to other time points), and though fell at 24 h, still at high level. The activated MPO rose at 6 h after reperfusion and peaked at 24 h ( P <0.05, compared to other time points). MIP 1 was positively correlated with MPO. CONCLUSION: NF κB may play an important role in PMNs infiltration by accelerating the expression of MIP 1 after focal cerebral ischemia reperfusion injury in rats.