应用MEA技术研究组织工程再造心肌对心梗大鼠心室肌电传导功能的影响

目的：应用微电极阵标测技术（MEA）研究组织工程再造心肌移植心梗大鼠的心肌电传导功能。方法：将成年SD大鼠30只随机分为假手术组、心梗组、移植组。应用MEA技术记录心室肌场电位的形态和激动传导时间。结果：正常大鼠心室除极波形多为三向波，呈RS、rSR’型。心梗组心梗面以QR或qR为主，R波圆钝；心室对立面及梗死周围面以R波为主。移植组心室心梗面主要以QR或qR为主，对立面及梗死周围区以Rs或R波为主。测量大鼠心室前壁、后壁及游离壁激动传导时间。假手术组为（6．5±2．12）ms、（11．25±1．77）nls和（7．05±0．78）ms；心梗组为（17．5±3．54）ms、（12．5±2．12）ms和（10．5±2．12）ms；移植组为（9．13±1．31）ms、（10．25±0．35）ms和（8．25±0．35）ms。与心梗组相比，移植组激动传导时间明显缩短（P〈0．05）。移植组和假手术组心梗面和周围面激动传导时间明显低于心梗组（P〈0．05）。结论：心肌细胞／胶原复合体可改善心梗组织的电传导功能。

Tissue-engineered myocardium transplantation on electrical-conduction in rats with myocardial infarction by MEA mapping technique

Objective：To study the effects of engineering heart tissue （EHT） transplantation on electrical-conduction in myocardial infarction （MI） by a new technique of microeletrode arrays （MEA）. Methods：Thirty SD rats of either sex weighting 220-250g were euthanized under chlorine hydrate 0.3ml/100mg anesthesia and were randomly divided into three groups： control group （n = 10）, MI group （n = 10） and transplantation group（n = 10）. The hearts were quickly removed and Langendorff-perfused with Tyrode＇s solution. We recorded field potential（FP） morphology and activation-conduction duration at local myocardium with microeletrode arrays technique. Results： The MEA detects clearly FP morphology. Most depolarization waves of cardiac ventricle were triphasic wave （RS, rSR＇ shape） in control group. Waves of infarction zone were mainly QR or qR wave, and waves of peri-infarction border and opposite zone were R wave in MI group. Waves of infarction zone were QR or qR wave, and waves of peri-infarction border and opposite zone were Rs or R wave in transplantation group. The activationconduction duration was （6.5 ± 2.12） ms in control group, （17.5 ± 3.54） ms in MI group, and （9.13 ± 1.31） ms in transplantation group. Compared with MI group, activation-conduction duration was significantly shortened in transplantation group （P〈0.05）, and was shorter in infarction zone and periinfarction border for control group and transplantation group than those for MI group （P〈0.05）. Conclusion：EHT transplantation improves the electrical-conduction function in MI rats.