icon pl   Patchliner application note:   logo pdf   (0.5 MB)
Cells were kindly provided by Charles River.
iCell® Cardiomyocytes2 were kindly provided by Fujifilm Cellular Dynamics International.


The voltage-gated Na+ channel 1.5 (NaV1.5) is encoded by the SCN5A gene and is responsible for the rising phase of the cardiac action potential (AP). The NaV1.5 channel is comprised of a pore-forming α subunit and auxillary β subunits. When the cardiac cell membrane depolarizes, NaV1.5 opens for a short time allowing an influx of Na+ ions resulting in the upstroke of the AP. During the AP, these channels can recover from inactivation and re-open resulting in a sustained current termed INa-Late. Although this current is substantially smaller than the peak Na+ current (INa-Peak), it is active during the plateau phase and therefore contributes to AP morphology. There is a growing body of evidence that increased INa-Late can have a pathophysiological role in acquired heart diseases such as myocardial ischemia and heart failure. INa-Late is elevated in several pathological conditions which could result in Na+-overload in these cells. A number of loss or gain-of-function mutations in the SCN5A gene have been identified which lead to changes in the magnitude or duration of INa-Peak or INa-Late resulting in fatal arrhythmias. INa-Late is a potential drug target to treat cardiac disorders such as angina, heart failure and arrhythmia. It is also an important target in safety pharmacology as enhancement of INa-Late is proarrhythmic.

In this study the Patchliner was used to record INa-Late from CHO cells and hiPSC-CMs. INa-Late was recorded using the voltage protocol specified by CiPA and activated using ATX-II. INa-Late could be recorded from CHO cells stably expressing NaV1.5 and blocked by lidocaine. INa-Late could also be detected in iCell® Cardiomyoctes2 and blocked by ranolazine.


We use cookies on our website. Some of them are essential for the operation of the site, while others help us to improve this site and the user experience (tracking cookies). You can decide for yourself whether you want to allow cookies or not. Please note that if you reject them, you may not be able to use all the functionalities of the site.