Simulation Of The Mechanosensitive Current And Its Effects On Myocyte-fibroblast Coupling

Cardiac fibroblasts can synthesis and maintain extracellular matrix. Increased quantities of extracelluar matrix produced by cardiac fibroblast can lead to cardiac fibrosis. Cardiac fibrosis can lead to atrial fibrillation and induce arrhythmias, so it is very meaningful to study fibroblast.Fibroblast is non-excitable cell, but it is sensitive to mechanical stimulus, mechanical deformation can change its electrophysiological properties. Cardiac fibroblast can coupling with cardiomyocyte and affect their electrical propertites. Each cardiomyocyte connects with at least one fibroblast. Experimental studies revealed that mechanosensitive ion currents exist in fibroblasts, but the effect of fibroblast on cardiomyocyte under mechanical environment has not been taken into consideration. The research work focuses on this issue, the detail works are as follows.First, a brief review of mechanosensitive currents which exist in cardiomyocyte, as well as a summary of common cardiomyocyte models and fibroblast model. Second we investigate effects of stretch-activated current on myocyte action potential, Based on the experimental data, we simulate the curve of the mechanosensitive current in fibroblast. Finally, we simulate the myocyte-fibroblast electrical coupling model including mechanosensitive currents, we observe the myocyte and fibroblast dynamic characteristics by modifying the parameters. When coupled with mechanosensitive fibroblasts, the action potential of myocyte duration was increased and so did the resting potential.The work of this thesis has important significance for further study of myocyte electrical properties under mechanical deformation.