Figure 2.

Simulation traces of the primary dynamic interactions of the M clock and Ca²⁺ clock during spontaneous production of action potential. Action potentials, major ionic currents and Ca²⁺ behaviors in different compartments were shown. Solid curves denoted the baseline (P_up =12mM/s, K_s =250/μs). Dashed curves were under the high SERCA pump rate (P_up =20mM/s, K_s =250/μs) while dotted curves corresponded to the high SERCA pump but low Ca²⁺ release rate (P_up =20mM/s, K_s =12.5/μs). Grey bars indicated the period of late DD under the baseline conditions. The jSRCarel curves inside the red circle were enlarged at the right side.