福辛普利钠预处理对缺血后适应大鼠心肌组织Toll样受体表达及炎症因子的影响

Effect of fosinopril sodium pretreatment on toll-like receptor and inflammatory factor in rat myocardium with ischemic postconditioning

大鼠预先灌胃福辛普利钠,观察其和缺血后适应(ischemic postconditioning,IPoC)对大鼠心肌缺血再灌注(ischemic reperfusion,I/R)损伤后心肌组织Toll样受体(toll-like receptor,TLR)表达及心肌组织炎症浸润的影响.将60只SD(Spragu-Dawley)大鼠随机分为假手术组、I/R组、IPoC组以及福辛普利钠+IPoC组,每组15只.假手术组大鼠心脏前降支下置线不结扎;I/R组予以心脏前降支结扎30min,再灌注1h;IPoC组给予心脏前降支结扎30min,后予以3次10s的再灌注/缺血循环,再持续灌注1h;福辛普利钠+IPoC组则预先给予福辛普利钠片0.9mg/kg,连续灌胃14d,于末次灌胃2h后,施以IPoC组的干预过程.所有实验大鼠腹主动脉取血并分离出心脏组织.比色法测定血清肌钙蛋白T(cardiac troponinT,cTNT)的含量,NBT染色测定大鼠左室心肌梗死面积,酶联免疫吸附测定法测定心肌组织单核细胞趋化蛋白-1(monocyte chemotactic protein-1,MCP-1)和肿瘤坏死因子-α(tumor necrosis factor-α,TNF-α)水平.免疫组织化学方法测定心肌组织TLR2及TLR4的表达,HE染色观察心肌组织炎性细胞的浸润.结果表明,与I/R组比较,IPoC组大鼠心肌梗死面积明显缩小(P<0.01),大鼠血清cTNT水平显著降低(P<0.01),心肌组织MCP-1,TNF-α含量和炎性细胞浸润数量明显下降(P<0.05,P<0.01),心肌组织TLR2及TLR4的表达被显著抑制(P<0.01);与IPoC组比较,福辛普利钠预处理可进一步降低IPoC大鼠心肌梗死面积(P<0.05),心肌组织TNF-α水平也显著降低(P<0.01),对心肌TLR2及TLR4的表达有进一步抑制(P<0.05).血管紧张素转化酶抑制剂福辛普利钠预处理可加强IPoC对I/R大鼠心肌的保护作用,其机理可能与抑制TLR介导的炎症信号通路和趋化因子反应有关.

To observe the effects of ischemic post-conditioning（IPoC） on Toll-like receptor expression and myocardial inflammatory infiltration in myocardial tissue of rats with ischemic reperfusion（I/R） injury and fosinopril sodium pre-treatment,a total of 60 Sprague-Dawley rats were randomly assigned to the following groups：sham（suture around left anterior descending coronary artery was not tied）,ischemic reperfusion（30 min in situ transient occlusion of the left anterior descending artery,followed by 1 h reperfusion）,IPoC（30-min occlusion of left anterior descending artery,followed by three cycles of 10-s reperfusion/10-s ischemia prior to 1-h reperfusion）,and fosinopril sodium ＋IPoC（fosinopril sodium pre-treatment,0.9 mg/kg,for 14 d,followed by 2-h I/R after last gavage,and IPoC treatment during I/R）.Arterial blood and heart samples were extracted after 1-h reperfusion.Serum cTnT levels were measured using the colorimetric method,myocardial infarct size was measured using nitrotetrazolium blue/chloride staining,TNF-α and MCP-1 levels in myocardial tissue were measured by ELISA.TLR2 and TLR4 expression in myocardial tissue was analyzed using immunohistochemistry,and infiltrating cells were detected by hematoxylin-eosin staining.Compared with the I/R group,myocardial enzyme cTnT levels and infarct size significantly decreased in the IPoC group（P 0.01）.In addition,MCP-1 and TNF-α levels,as well as the number of infiltrating cells in myocardial tissue,significantly decreased（P 0.05,P 0.01,respectively）.TLR2 and 4 expressions also significantly decreased in the IPoC group（P 0.05,P 0.01,respectively）.Compared with the IPoC group,the combination of fosinopril sodium and IPoC further reduced infarct size（P 0.05）,as well as TNF-α levels in myocardial tissue（P 0.01）.TLR2 and 4 expressions and infiltration of inflammatory cells were also significantly decreased（P 0.05）.Therefore,fosinopril sodium enhanced the protective effect of IPoC in a rat model of myocardial I/R injury.These mechanisms could be related to inhibition of the TLR signal pathway and chemotactic factor reactions.