Effect of Ca²⁺ Efflux Pathway Distribution and Exogenous Ca²⁺ Buffers on Intracellular Ca²⁺ Dynamics in the Rat Ventricular Myocyte: A Simulation Study

Figure 2

Effect of partial localization of NCX exchange (a), sarcolemmal Ca²⁺ pump (b), and SERCA (c) at the dyads on the time course of total 𝐼_NaCa, 𝐼_pCa, 𝐽_up, and 𝐼_Ca and Ca²⁺ transients in the t-tubular dyadic space ([Ca²⁺]_dt) and in the cytosol ([Ca²⁺]_c) during a steady-state cycle at 5 Hz (action potentials elicited by 1 ms current clamps). The solid and dashed lines, respectively, represent traces obtained in control conditions (𝑓_NaCa,d=𝑓_pCa,d=𝑓_up,d=0) and when𝑓_NaCa,d, 𝑓_pCa,d, or 𝑓_up,d was separately increased to 0.3.

(a)

(b)

(c)