Rigidity-matching between cells and the extracellular matrix leads to the stabilization of cardiac conduction
M. Hörning, S. Kidoaki, T. Kawano, and K. Yoshikawa
Biophysical Journal, 102, 379–387, 2012 - doi : 10.1016/j.bpj.2011.12.018
Brief Summary: ''...We found that myocardial conduction is significantly promoted when the rigidity of the cell culture environment matches that of the cardiac cells (ETissue = EECM = 12 kPa). The stability of spontaneous target wave activity and calcium transient alternans in high frequency-paced tissue were both enhanced when the cell substrate and cell tissue showed the same rigidity. We conclude that rigidity matching in cell-to-substrate interactions critically improves cardiomyocyte-tissue synchronization, suggesting that mechanical coupling plays an essential role in the dynamic activity of the beating heart. ...''
Negative Curvature Boundaries as Wave Emitting Sites for the Control ￼￼of Biological Excitable Media
P. Bittihn*, M. Hörning and S. Luther
Physical Review Letters, 109, 118106, 2012 - doi : 10.1103/PhysRevLett.109.118106
Brief Summary: ''... On the basis of a bidomain description, a unified theory for the electric-field-induced depolarization of the substrate near curved boundaries of generalized shapes is provided, resulting in the localized recruitment of control sites. The findings are confirmed in experiments on cardiomyocyte cell cultures and supported by two-dimensional numerical simulations on a cross section of a rabbit ventricle. ...''