Effect of Ca2+ Efflux Pathway Distribution and Exogenous Ca2+ Buffers on Intracellular Ca2+ Dynamics in the Rat Ventricular Myocyte: A Simulation Study
Figure 6
(a) Inactivation of in the presence of intracellular EGTA (5 mM) or BAPTA (10 mM) in rat ventricular myocytes (adopted from [15]); was recorded during a 200 ms depolarising pulse from −80 mV to 0 mV at room temperature. The kinetics of inactivation were characterized by the time required for the current to decay to 0.37 of its peak amplitude (). The lower panel shows that inactivation was substantially slowed in the presence of 10 mM BAPTA: ms versus 16.4 ms in the presence of 5 mM EGTA. 1 mM Ba was used to show the time course of in the absence of -dependent inactivation. (b) Reconstruction of experimentally observed effect of EGTA and BAPTA on inactivation in the model. The top panel shows superimposed normalized responses of in control conditions and with 5 mM EGTA and 10 mM BAPTA. The lower panel shows corresponding values of .
