Jacquemet Vincent
Signal Processing Institute, Ecole Polytechnique Fédérale de Lausanne, CH-1015 Lausanne, Switzerland.
Phys Rev E Stat Nonlin Soft Matter Phys. 2006 Jul;74(1 Pt 1):011908. doi: 10.1103/PhysRevE.74.011908. Epub 2006 Jul 14.
Fibroblasts are nonexcitable cells that are sometimes coupled with excitable cells (cardiomyocytes). Due to a higher resting potential, these cells may act as a current source or sink and therefore disturb the electrical activity of the surrounding excitable cells. The possible occurrence of spontaneous pacemaker activity resulting from these electrotonic interactions was investigated in a theoretical model of two coupled cells as well as in a multicellular fiber model based on the Courtemanche kinetics. The results indicate that repeated spontaneous activations can be observed after an alteration in the activation and recovery properties of the sodium current (changes in excitability properties), provided that the difference in the resting potential as well as the coupling between the excitable and nonexcitable cells is sufficiently high. This may constitute a mechanism of focal sources triggering arrhythmias such as atrial fibrillation.
成纤维细胞是不可兴奋细胞，有时与可兴奋细胞（心肌细胞）耦联。由于静息电位较高，这些细胞可能充当电流源或电流汇，从而干扰周围可兴奋细胞的电活动。在两个耦联细胞的理论模型以及基于Courtemanche动力学的多细胞纤维模型中，研究了由这些电紧张相互作用导致的自发起搏器活动的可能发生情况。结果表明，在钠电流的激活和恢复特性发生改变（兴奋性特性改变）后，只要静息电位差异以及可兴奋细胞与不可兴奋细胞之间的耦联足够大，就可以观察到反复的自发激活。这可能构成触发心律失常（如心房颤动）的局灶性来源的一种机制。
