Hong Zhang
School of Electrical Engineering, Xi`an Jiaotong University, 710049, Xi`an, China
Xin Huang
Department of Cardiology, The First Hospital, Xi`an Jiaotong University, 710061, Xi`an, China
Dan Zhao
School of Electrical Engineering, Xi`an Jiaotong University, 710049, Xi`an, China
ABSTRACT
Late sodium current INaL is largely enhanced in failure and ischemic hearts. However, its role in the failure in combination with ischemic heart is poorly understood. In this study, a transmural computer model was created by considering the most significant effect of ischemia on different cellular types along the fiber. By completely blocking IKr while enhancing INaL, the low repolarization reserve situations in Heart Failure (HF) were also simulated. The results showed that when INaL was elevated 4 times, repolarization and Transmural Dispersion of Repolarizing (TDR) were both enlarged with rate dependence. Further enhancement of INaL could amplify the rate adaptation. For 5 relative to 4 times INaL, TDR raised 14.5, 18.3 and 21.5% for basic cycle lengths of 500, 1000 and 2000 m sec, respectively. Moreover, Early After Depolarization (EAD) could be induced by enlarging INaL to 10 times while considering a 4-fold increase of L-type calcium current ICaL to mimic adrenergic stimulation observed in HF. Therefore, the study indicated that in failure in combination with ischemic heart, the enhancement of INaL could favor the occurrence of either the reentrant or the triggered arrhythmia. Accordingly, selective blockade of INaL was suggested to be a potential target for antiarrhythmic therapy.
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How to cite this article
Hong Zhang, Xin Huang and Dan Zhao, 2013. Role of Late Sodium Current in the Simulated Low Repolarization Reserve
and Ischemic Ventricular Tissue. Biotechnology, 12: 104-108.
DOI: 10.3923/biotech.2013.104.108
URL: https://scialert.net/abstract/?doi=biotech.2013.104.108
DOI: 10.3923/biotech.2013.104.108
URL: https://scialert.net/abstract/?doi=biotech.2013.104.108
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