心肌缺血再灌注中肿瘤坏死因子-α表达及多层次的心肌保护

An experimental study on TNF-α expression and multiple prectections in myocardial ischemic-reperfusion injury

目的 研究①心肌缺血 再灌注时心肌组织肿瘤坏死因子 -α(TNF α)表达与心肌核因子 κΒ(NF κB)活化之间的关系 ;②抗肿瘤坏死因子 α单克隆抗体 (Anti-TNF -α -mAb)及吡咯基二硫氨基甲酸酯 (PDTC)的心肌保护作用。方法 新西兰兔 2 48只分为①缺血 再灌注组 (IR) :结扎免左冠状动脉前降支造成心肌缺血 45分钟后再开放 ,②PDTC预处理组 :在心肌缺血前 10分钟静脉注射PDTC(15mg/kg) ;③Anti-TNF -α -mAb预处理组 :在心肌缺血前 10分钟静脉注射(Anti -TNF -α -mAb) (2mg/Kg) ;④多层预处理组 :在心肌缺血前 10分钟静脉注射Anti ΤΝF α mAb及PDTC(量同前 ) ;⑤假手术对照组 (Sham)。每组又分缺血前 (0 ) ,再灌注后 3 0、60、90、12 0、2 40、3 60分钟时相点。用酶联免疫吸附实验 (ELISA)测定心肌组织中TNF α的表达 ,凝胶电泳迁移率 (ESMA)分析检测心肌组织NF -κB的活性 ,髓过氧化酶法 (MPO)定量测定心肌组织中浸润的中性粒细胞。结果 与缺血前比较 ,在缺血 再灌注组中心肌再灌注 3 0分钟后NF -kB活性开始增高。 12 0分钟达到高峰 ,之后活性有所下降 ,但仍明显高于缺血前 (P <0 0 5 ) ;心肌TNF α的表达在心肌再灌注 12 0分钟明显增高 (P <0 0 5 ) ,并持续保持在高水平状态 ,并与中性粒细?

Objective To study the relationship between the TNF a expression of myocardium and the activation of nuclear factor κB(NF κB) and determine the prectective effects of Anti Tumor necrosis factor α moloclonal antibody(Anti TNF α mAb)and Pyrrolidine dithiocarbamate(PDTC)in myocardial ischemic reperfusion Methods Two hundred and forty eight Newzeland rabbits were divided into five groups:①Ischemia Reperfusion group(IR group):Rabbits were subjected to total occlusion of left anterior descending artery for 45 min(LAD)and then followed by reperfusion;②Anti TNF α mAb Preconditioning group:Rabbits were pretreated with tumor necrosis factor a antibody 2 mg/kg at 10 min before ischemia;③PDTC Prconditioning group:Rabbits were pretreated with PDTC 15mg/kg at 10 min before ischemia;④Anti TNF α mAb and PDTC Proconditioning group;⑤Sham group The myocardial samples were studied at baseline (0) before ischemia and,30,60,90,120,240,360 min after ischemia reperfusion The expression levels of TNF α were evaluated by enzyme linked immunosorbent assay(ELISA),and activation of NF κB by electrophoretic mobility shift assay(EMSA),the infiltration of PMN were measured by MPO Results In IR group,after ischemia reperfusion for 30 min,activation of NF κB increased significantly and reached a peak at 120 min,then decreased;the expression levels of TNF α of myocardium increased at 120 min and maintained the high level,the expression levels of TNF-α had positive correlation to the infiltration of PMN;PDTC or Anti TNF α mAb could inhibt the activation of NF κB,expresion of TNF α and infiltration of PMN But they all could do better than any single one of them Conclusion The inducible activation of NF κB starts up TNF α expression and TNF α has an important positive feedback effect on the activation of NF κB in myocardial ischemic reperfusion injury PDTC?Anti TNF α mAb is able to inhibit expresion of TNF α in different way and all of them con do better than any single one