制备大鼠离体心脏损伤模型的最佳缺血再灌注时间

Optimal time choice of ischemia-reperfusion in the preparation of isolated heart injury model

目的探索离体心脏最佳缺血再灌注(I/R)时间,增加制备可用于心肌保护药物的方法筛选的离体心脏I/R模型的成功率。方法采用Langendorff离体心脏恒压灌流模式,缺血31 min后,分别于再灌5,10,20和30 min时测定心电图、左心室压力(LVP)、冠脉流量(CF)、左心室舒张末期压(LVEDP)和收缩末期压(LVESP);观察心律失常发生率,计算左心室发展压(LVDP)、收缩期舒张期左心室内最大上升/下降速率(±dp/dtmax)和心率(HR)。结果离体心脏再灌后HR和CF低于停灌前,差异显著(P<0.05);停灌期间,LVEDP升高,心肌挛缩。再灌时90%心脏可成功自主复跳,100%复跳心脏出现心律失常(室速或室颤),持续约5～10 min。再灌后LVDP下降、左心室最大舒缩速度下降。结论停灌31 min,再灌30 min可成功制备出用于药物筛选的离体心脏I/R损伤模型。

OBJECTIVE To explore a suitable time for ischemia-reperfusion injury model preparation. METHODS The rat heart was isolated and perfused retrogradely using the Langen- dorff method at a constant pressure, the electrocardiogram（ ECG）, left ventricular pressure（ LVP）, coronary flow（CF）, left ventricular end diastolic pressure（ LVEDP）, left ventricular end diastolic pressure （LVEDP）, and the rate of arrhythmia were estimated and the left ventricular developed pressure（ LVDP）, maximum rate of increase in left ventricular pressure （ ＋ dp/dtmax ）, maximum rate of decrease in left ventricular pressure （ - dp/dtmax ） and the heart rate （HR） were calculated at 5, 10, 20 and 30 min. RESULTS Compared with pre-ischemia, the reperfusion caused significant decrease in CF and HR （P 〈 0.05 ） and a marked depression in cardiac function as indicated by an obvious decrease in LVDP,±dp/dtmax, and a marked elevation in LVED after reperfusion （P 〈0.01 ）. CONCLUSION The optimal time for model preparation is ischemia for 31 min followed by 30 rain reperfusion.