Different Densities of Na-Ca Exchange Current in T-Tubular and Surface Membranes and Their Impact on Cellular Activity in a Model of Rat Ventricular Cardiomyocyte

Figure 2

Action potential, , and Ca²⁺ concentration changes in the network compartment of SR (), submembrane spaces (surface: , t-tubular: ), and the cytosol () during 0.2 s of steady-state stimulation cycle (after 600 s) at 0.1 and 1 Hz. The full line stands for the simulations performed in the control model ( set to 0.78). The dashed and dotted lines, respectively, stand for the simulations done when was set to 0.48 and 0.93 (corresponds to -ratio of 1.7 and 25, resp.).