微电极阵芯片技术在心肌电生理研究中应用的可行性

Mapping of field action potential by microelectrode arrays mapping system

目的探讨60极微电极阵芯片(MEA)技术在整体心脏、心肌组织片和培养心肌等电生理研究中的应用。方法①80只豚鼠,开胸取心脏并以2.5ml/min速度Langendorff灌流心脏20min,信号稳定后采样;②60只SD大鼠,开胸取心,剪取5mm×5mm大小的心脏组织片,置于MEA盘,台氏液间歇灌流5min,用5μV×1ms的刺激脉冲连续刺激,刺激间隔为1s,比较心房和心室组织片场电位(FPs)形态和传导时间;③20窝出生后3天以内的昆明小白鼠,消化分离心肌细胞,培养于MEA盘内,进行组织信号采样。结果①大鼠整体心脏灌流30～90min内能够记录到稳定的自主节律下的FPs信号,心室肌场电位时程(FPdur)210±78ms;心房肌FPdur164±58ms;房室传导时间320±150ms;并能记录到FPs激动顺序图。②心肌组织靶点取样,台氏液间歇灌流和电刺激下,组织的兴奋性可以稳定保持2h。心室肌组织片FPdur115.80±11.61ms,心房组织片FPdur83.71±6.48ms,刺激信号在心房组织片的传导时间66.46±6.73ms,心室组织片传导时间47.40±5.62ms;③小鼠乳鼠心脏原代培养心肌24h时后开始有散在、不同步的细胞克隆搏动和点状FPs信号,72h后细胞融合,开始记录到基本同步的群动和多位点FPs信号,培养心肌自发搏动频率150±100次/分。结论 MEA技术可以稳定记录小动物整体灌流心脏,心脏定点取样组织片,培养心肌细胞60极场电位和电传导特性。

Objective To study the field potentials （FPs）systemically by 60 microelectrode arrays mapping system （MEA）. Methods （1）Eighty adult guinea pigs were anesthesiaed. The hearts were quickly removed for recording the FPs;（2）Sixty SD rats were anesthesiaed. The hearts were quickly removed and Langendorff-perfused. FPs were recorded by 51μV × 1ms electric stimulus in tissue slice. （3）Myocytes from embryonic mice heart were isolated and cultured. FPs were recorded after cells were cultured for 24 h and 72 h. Results （1）The MEAs technique could stably record FPs in Langendorff-perfused whole heart of SD rat for 30 -90 minites, the FPs of both ventricular and atrial were 210 ± 78 ms and 164 ± 58 ms, and the atrial-ventricular conduction time was 320 ＋ 150 ms. （2）The MEA recorded FPs in perfused heart tissues of SD rat for 2 h. The FPs of both ventricular and atrial tissue slices was 115.80 ± 11.61 ms and 83.71 ± 6.48 ms. （3）The MEA recorded FPs in cultured myocytes from embryonic mice heart. Conclusion MEAs is a sensitive,long time and stable local tissue action potential muhiple-channel recording mapping system not only in cultured myocytes but also in small animal whole heart and tissue slices. [ Chinese Journal of Cardiac Pacing and Electrophysiology,2010,24（2） ：152 -155 ]