ABSTRACT

Mathematical models for the action potential (AP) generation of the electrically excitable cells including the heart are involved different mechanisms including the voltage-dependent currents with nonlinear time- and voltage-gating properties. From the shape of the AP waveforms to the duration of the refractory periods or heart rhythms are greatly affected by the functions describing the features or the quantities of these ion channels. In this work, a mathematical measure to analyze the regional contributions of voltage-gated channels is defined by dividing the AP into phases, epochs, and intervals of interest. The contribution of each time-dependent current for the newly defined cardiomyocyte model is successfully calculated and it is found that the contribution of dominant ion channels changes substantially not only for each phase but also for different regions of the cardiac AP. Besides, the defined method can also be applied in all Hodgkin–Huxley types of electrically excitable cell models to be able to understand the underlying dynamics better.

摘要

包括心脏在内的电可兴奋细胞的动作电位 (AP) 生成的数学模型涉及不同的机制，包括具有非线性时间和电压门控特性的电压相关电流。从 AP 波形的形状到不应期或心律的持续时间，都受到描述这些离子通道特征或数量的函数的极大影响。在这项工作中，通过将 AP 划分为感兴趣的阶段、时期和间隔来定义分析电压门控通道区域贡献的数学度量。成功计算了每个时间相关电流对新定义的心肌细胞模型的贡献，发现主要离子通道的贡献不仅在每个阶段而且对心脏 AP 的不同区域都有显着变化。此外，定义的方法还可以应用于所有 Hodgkin-Huxley 类型的电可激发细胞模型，以便能够更好地理解潜在的动力学。