皮瓣缺血再灌注期间核因子-κB活性的变化及其意义

The significance of nuclear factor-κB activation in ischemia-reperfusion injury of inguinal island skin flaps in rats

目的 探讨核因子(NF) κB活性变化在皮瓣缺血再灌注(I/R)损伤中的作用。方法将60只雄性SD大鼠随机分为3组:对照组;I/R组;吡咯烷二硫氨基甲酸酯(PDTC)处理组。制备右下腹岛状皮瓣I/R模型。PDTC处理组于再灌注前及早期,分2次静脉注射PDTC(3 0 0mg/kg体重)。采用免疫组织化学及凝胶电泳迁移率法,检测皮瓣NF κB活化情况,并行组织学观察。结果 I/R组再灌注后NF κBp65阳性细胞较对照组明显增加,NF κB活性于再灌注1、3h显著增强;PDTC处理组再灌注1、2h阳性细胞数(7.90±3 .73、10 .60±3 .2 0 )较I/R组(19.5 0±6.93、18.5 0±5 .68)明显减少(P均<0 .0 1) ,再灌注1hNF κB活性受到抑制,中性粒细胞浸润及组织水肿程度较I/R组明显改善。结论 NF

Objective To determine whether nuclear factor-κB (NF-κB) is activated in the ischemia-reperfusion (I/R) model of ratskin flaps and the effects of NF-κB inhibition on I/R injury.Methods The inguinal island skin flaps based on the superficial inferior epigastric vessels were divided into three groups:control group,I/R group and PDTC-treated group.In both I/R and PDTC-treated group,flaps were subjected to 10 h of warm ischemia.A bolus of PDTC (300 mg/kg) was infused intravenously 5 min before reperfusionm,followed by a second dose during the first 30 min of reperfusion in PDTC-treated group.NF-κB binding activity in flap tissue was analyzed at 1,2,3 and 6 h of reperfusion by immunohistochemical technique and electrophoretic mobility shift assay (EMSA).The flaps were assessed histologically at 6 h of reperfusion.Results The positive staining cells were significantly higher in I/R group than in the control group after reperfusion.Few positive staining cells were observed in PDTC-treated group at 1 and 2 h of reperfusion as compared with I/R group (7.90± 3.73 and 10.60± 3.20 versus 19.50± 6.93 and 18.50± 5.68, P < 0.01). NF-κB was activated at 1 and 3 h of reperfusion inI/R group and NF-κB binding activity was significantly suppressed in PDTC-treated group at 1 h of reperfusion.Marked neutrophil infiltration and edema was observed in I/R group,while less neutrophil infiltration was observed in PDTC-treated group.Conclusion Activation of NF-κB may play an important role in the I/R injury of island skin flap.