恒定磁场对大鼠心肌缺血/再灌注损伤和无复流面积的影响

Effect of constant magnetic field on myocardial ischemia-reperfusion injury and no-reflow area in rats

目的:观察恒定磁场干预对大鼠心肌缺血/再灌注损伤和无复流面积的影响.方法:将24只雄性SD大鼠随机分为4组:假手术组、缺血/再灌注组、50mT恒定磁场+缺血/再灌注组及100mT恒定磁场+缺血/再灌注组,每组6只.大鼠麻醉开胸,结扎冠状动脉前降支40min,再灌注4h.采用硫黄素染色评估缺血心肌再灌注后的无复流面积,Evan′s蓝和氯化三苯基氮四唑(TTC)染色法测定心肌梗死范围;全自动生化分析仪测定血清肌酸激酶(CK)的水平,微粒子化学发光法测定血清肌钙蛋白I(cTnI)的水平.结果:50mT及100mT恒定磁场干预组的心肌梗死面积和无复流面积显著小于缺血/再灌注组(P<0.05).缺血/再灌注组大鼠血清CK和cTnI的水平与假手术组比较显著升高(P<0.05);而不同强度的恒定磁场干预+缺血/再灌注组血清CK和cTnI的水平与缺血/再灌注组比较显著降低(P<0.05).结论:恒定磁场干预可减轻缺血/再灌注所致大鼠心肌的损伤和无复流面积.

AIM： To investigate the effect of constant magnetic field （CMF） on myocardial ischemia/reperfusion injury （IRI） and no-reflow area in rats. METHODS：Twenty-four male Spragne-Dawley rats were randomly divided into 4 groups： sham operation group, IRI group, 50 mT CMF intervention group and 100 mT CMF intervention group, with 6 in each group. The rats were anesthetized and then underwent 40 min of myocardial ischemia and 4 h of reperfusion. Size of no-reflow area was determined by thioflavin-S. The infarct size was assessed by Evans＇ blue and TTC staining. Level of sera cardiac troponin I （ cTn I） was detected by ehemiluminescent enzyme immunoassay. Level of sera ereatine kinase （CK） was determined by automatic biochemistry analyzer. RESULTS ： The ratio of infarct size to area at risk （ IS/ AAR） and size of no-reflow area decreased following intervention with 50 mT or 100 mT CMF, which were significantly smaller than those in IRI group （P 〈 0.05）. Levels of sera CK and cTnI in IRI group were significantly higher than those in sham operation group （ P 〈 0.05 ） , whereas levels of sera CK and cTnI in 50 mT or 100 mT CMF intervention group were significantly lower than those in IRI group （ P 〈 0.05 ）. CONCLUSION ： Intervention with CMF could protect the heart against IRI and no-reflow.