拍動時の細胞膜電位変動に基づく電気刺激が心筋細胞分化に及ぼす影響

抄録

In the field of myocardial regeneration, various external electrical stimuli have been reported to improve the efficiency for myocardial differentiation. It also has been reported that the intracellular ionic fluctuations caused by cardiomyocyte pulsation were propagated to the fibroblastic cells surrounding the beating cardiomyocytes. However, it is unknown whether these intracellular electrical signals can affect the differentiation of undifferentiated cardiomyocytes. In this study, we focused on effects of changes in the cell membrane potential generated by cardiomyocyte pulsation on the cardiac differentiation of P19CL6 cells. We fabricated a cultured device that can electrically stimulate cells using an indium tin oxide (ITO) glass. By using membrane voltage indicator, changes in the luminance of beating cells were evaluated, and an external electrical stimulation waveform was constructed based on the variation of the time-dependent luminance values. The period from the start of depolarization to the recovery to the resting membrane potential was set at 300 ms. It was found that the electrical stimulation based on the wave of the membrane potential promoted the expression time and number of beating colonies and decreased the deviation of colony size, compared to that of single-phase pulse waveform. These results suggest that the electrical signal originated from the changes in the cell membrane potential promoted the myocardial differentiation.