缺血后处理对猪体外循环手术心肌肌钙蛋白Ⅰ及肌酸激酶同功酶的影响

Effect of ischemic postconditioning on cTn I and CKMB in pigs during open-heart surgery

目的探讨缺血后处理对猪心肌肌钙蛋白Ⅰ(cTnⅠ)及肌酸激酶同功酶(CKMB)的影响。方法24只小型约克猪(体重35～40 kg)被随机分为4组。A组:于体外循环(cPB)开始后并行循环45 min,心肌缺血90 min,再灌注120 min;B组:升主动脉阻断前进行心脏缺血预处理(阻断升主动脉5 min、开放10 min,重复3次),余处理与A组相同;C组:并行循环45 min,心肌缺血90 min,再灌注120 min;再灌注开始进行缺血后处理(阻断升主动脉30 s后开放30 s,重复3次,共3 min);D组:缺血预处理+缺血后处理。在CPB前、缺血90分、再灌注30、60、90、120 min采静脉血检测血cTn。、CKMB水平。结果在再灌注30、60、90、120 min,A组cTn。和CKMB分别为5.41、6.63、8.84、13.25μg/L和18.61、21.53、25.54、29.73μg/L,B组分别为2.61、2.97、4.60、5.97μg/L和12.45、13.68、15.50、14.18μg/L,C组分别为3.01、3.21、4.68、5.92μg/L和14.01、14.51、16.48、16.71μg/L,D组分别为2.63、3.06、4.68、6.04μg/L和13.08、14.20、15.18、15.86μg/L;血浆cTnⅠ和CKMB水平在B组、C组及D组显著低于A组(P<0.05),而B组和C组与D组无统计学意义(P>0.05)。结论缺血后处理可以抑制cTnⅠ的释放和CKMB漏出,减轻心肌缺血再灌注损伤而发挥心肌保护作用。

Objective To investigate the effect of ischemic postconditioning on cTn Ⅰ and CKMB in pigs during open-heart surgery. Methods Twenty - four Yorkshire pigs weighing 35-40 kg were divided into 4 groups： group A,a run pump for 45 min prior to the aortic cross-clamping （ACC） ,then with 90 min ACC followed by 120 min reperfusion;group B,with 90 min ACC followed by 120 rain reperfusion, three cycles,5 min of ischemia,each followed by 10 rain of reperfusion before ACC;group C, with 90 min ACC followed by 120 min reperfusion ,reperfusion was initiated for 30s of reperfusion followed by 30s of reocclusion,repeated for three cycles （3 min total intervention） ;Group D： ischemic preconditioning ＋ ischemic postconditioning. Blood samples were taken for detection of serum cTn I ,CKMB at the following time points： before CPB;90 min after ischemia;30,（d）,90,120 min after reperfusion. Results cTnⅠ and CKMB during reperfusion were significantly lower in group B （2.61,2.97,4.60,5.97μg/L and 12.45,13.68,15.50,14.18 μg/L） ,group C （ 3.01,3.21,4.68,5.92μg/L and 14.01,14.51,16.48, 16.71 μg/L）and group D （2.63,3.06,4.68,6.04 μg/L and 13.08,14.20,15.18,15.86μg/L） than in group A （5.41,6.63,8.84,13.25μg/L and 18.61,21.53,25.54,29.73 μg/L） （P 〈0.05）. However,there was no significant difference in cTn Ⅰ and CKMB during reperfusion between group C and group B,group D （P 〉 0. 05 ）. Conclusion Isehemie postconditioning at the beginning of reperfusion might relieve ischemic reperfusion injury by reducing CKMB leakage and cTnⅠ release.