Synchronization of Large Clusters of Cardiomyocytes Connected by Fibroblasts

Abstract

To analyze the synchronization process of clusters of chicken embryo-derived cardiomyocytes, we used the on-chip multi electrode arrays (MEA) system with agarose microchambers. In previous studies of the mouse-derived cardiomyocytes, it is known that fibroblasts propagate action potential if the distance is within 300μm. In addition, in the synchronization process of a single cardiomyocyte, it is also known that a cell with stable beating becomes pacemaker. Two sets of cardiomyocyte clusters were connected with fibroblasts by additional agarose micro fabrication during cell culture, and fibroblasts distance changed 600 μm, 300 μm, 150 μm. For evaluating synchronization, we used three indication that Inter Spike Interval ( ISI ), Coefficient of Variation ( CV ), Delay time. ISI represents beating rate of cardiomyocytes clusters, and it measured each 1 minutes every 10 minutes until beating stopped. CV represents fluctuation of the beating. In the two sets of clusters, we were elected each channel which is suitable for the analysis. For the analysis of the data, we used “ MATLAB ”.As a result, clusters of chicken embryo-derived cardiomyocytes were synchronized within the fibroblast distance of 300 μm, and pace making is not depended on the fast beating rate or the stability of fluctuation. It was suggested that anather mechanism of synchronization between large size clusters of cardiomyocyte exists different from tissues or single cardiomyocytes.