Prajapati Chandra, Pölönen Risto-Pekka, Aalto-Setälä Katriina
BioMediTech, University of Tampere, 33520 Tampere, Finland.
BioMediTech, University of Tampere, 33520 Tampere, Finland
Biol Open. 2018 Jul 16;7(7):bio035030. doi: 10.1242/bio.035030.
Human induced pluripotent stem cell derived cardiomyocytes (hiPSC-CMs) offer a unique platform to study cardiac diseases, as they recapitulate many disease phenotypes. The membrane potential (V) and intracellular calcium (Ca) transient (CaT) are usually investigated separately, because incorporating different techniques to acquire both aspects concurrently is challenging. In this study, we recorded V and CaT simultaneously to understand the interrelation between these parameters in hiPSC-CMs. For this, we used a conventional patch clamp technique to record V, and synchronized this with a Ca imaging system to acquire CaT from same hiPSC-CMs. Our results revealed that the CaT at 90% decay (CaT90) was longer than action potential (AP) duration at 90% repolarization (APD90). In addition, there was also a strong positive correlation between the different parameters of CaT and AP. The majority of delayed after depolarizations (DADs) observed in the V recording were also characterized by elevations in the intracellular Ca level, but in some cases no abnormalities were observed in CaT. However, simultaneous fluctuations in CaT were always observed during early after depolarizations (EADs) in V In summary, simultaneous recording of V and CaT broadens the understanding of the interrelation between V and CaT and could be used to elucidate the mechanisms underlying arrhythmia in cardiac disease condition.
人诱导多能干细胞衍生的心肌细胞（hiPSC-CMs）为研究心脏疾病提供了一个独特的平台，因为它们能够重现许多疾病表型。膜电位（V）和细胞内钙（Ca）瞬变（CaT）通常是分开研究的，因为同时采用不同技术来获取这两个方面具有挑战性。在本研究中，我们同时记录V和CaT，以了解hiPSC-CMs中这些参数之间的相互关系。为此，我们使用传统的膜片钳技术记录V，并将其与钙成像系统同步，以从相同的hiPSC-CMs中获取CaT。我们的结果显示，90%衰减时的CaT（CaT90）比90%复极化时的动作电位（AP）时程（APD90）更长。此外，CaT和AP的不同参数之间也存在很强的正相关。在V记录中观察到的大多数延迟后去极化（DADs）也表现为细胞内钙水平升高，但在某些情况下，CaT未观察到异常。然而，在V中的早期后去极化（EADs）期间总是观察到CaT的同时波动。总之，V和CaT的同步记录拓宽了对V和CaT之间相互关系的理解，并可用于阐明心脏疾病状态下心律失常的潜在机制。
