Department of Physiology, School of Biomedical Sciences, University of Melbourne, Melbourne, Victoria, Australia.
Institute of Cardiovascular Sciences, College of Medical and Dental Sciences, University of Birmingham, United Kingdom.
Am J Physiol Cell Physiol. 2019 Dec 1;317(6):C1256-C1267. doi: 10.1152/ajpcell.00306.2019. Epub 2019 Oct 2.
Cardiac arrhythmias of both atrial and ventricular origin are an important feature of cardiovascular disease. Novel antiarrhythmic therapies are required to overcome current drug limitations related to effectiveness and pro-arrhythmia risk in some contexts. Cardiomyocyte culture models provide a high-throughput platform for screening antiarrhythmic compounds, but comparative information about electrophysiological properties of commonly used types of cardiomyocyte preparations is lacking. Standardization of cultured cardiomyocyte microelectrode array (MEA) experimentation is required for its application as a high-throughput platform for antiarrhythmic drug development. The aim of this study was to directly compare the electrophysiological properties and responses to isoproterenol of three commonly used cardiac cultures. Neonatal rat ventricular myocytes (NRVMs), immortalized atrial HL-1 cells, and custom-generated human induced pluripotent stem cell-derived cardiomyocytes (hiPSC-CMs) were cultured on microelectrode arrays for 48-120 h. Extracellular field potentials were recorded, and conduction velocity was mapped in the presence/absence of the β-adrenoceptor agonist isoproterenol (1 µM). Field potential amplitude and conduction velocity were greatest in NRVMs and did not differ in cardiomyocytes isolated from male/female hearts. Both NRVMs and hiPSC-CMs exhibited longer field potential durations with rate dependence and were responsive to isoproterenol. In contrast, HL-1 cells exhibited slower conduction and shorter field potential durations and did not respond to 1 µM isoproterenol. This is the first study to compare the intrinsic electrophysiologic properties of cultured cardiomyocyte preparations commonly used for in vitro electrophysiology assessment. These findings offer important comparative data to inform methodological approaches in the use of MEA and other techniques relating to cardiomyocyte functional screening investigations of particular relevance to arrhythmogenesis.
心脏的房性和室性心律失常是心血管疾病的一个重要特征。需要新的抗心律失常疗法来克服当前药物在某些情况下的有效性和致心律失常风险的局限性。心肌细胞培养模型为筛选抗心律失常化合物提供了高通量平台，但缺乏关于常用类型的心肌细胞制剂的电生理特性的比较信息。为了将心肌细胞微电极阵列（MEA）实验标准化为高通量抗心律失常药物开发平台，需要对其进行标准化。本研究的目的是直接比较三种常用心脏培养物的电生理特性和异丙肾上腺素反应。原代培养的新生大鼠心室肌细胞（NRVMs）、永生化的心房 HL-1 细胞和定制生成的人诱导多能干细胞衍生的心肌细胞（hiPSC-CMs）在微电极阵列上培养 48-120 小时。在存在/不存在β-肾上腺素能激动剂异丙肾上腺素（1µM）的情况下，记录细胞外场电位，并绘制传导速度图。NRVMs 的场电位幅度和传导速度最大，且来源于雄性/雌性心脏的心肌细胞之间没有差异。NRVMs 和 hiPSC-CMs 的场电位持续时间均随频率依赖性而延长，并对异丙肾上腺素有反应。相比之下，HL-1 细胞的传导速度较慢，场电位持续时间较短，且对 1µM 异丙肾上腺素没有反应。这是首次比较常用于体外电生理学评估的培养心肌细胞制剂的固有电生理特性的研究。这些发现提供了重要的比较数据，可用于告知 MEA 和其他与心肌细胞功能筛选调查相关的技术的方法学方法，这些方法对于心律失常发生具有特别重要的意义。
