Fig. 8.
PVC genesis modulated by other factors. In each panel, the PVC zone in Fig. 4B was taken as control and colored gray. The PVC zone after a parameter change was colored green. Because the green was set to be semitransparent, the color became darker when the PVC zone overlapped with that of the control. A: normal [LQT2 + the rapid component of the delayed-rectifier potassium current (IKr)]. B: reduced gap junction coupling (from 0.0005 to 0.0001 ms/cm2). C: reduced peak Na current (INa) by reducing the maximum conductance (from 12 to 8 mS/μF). D: hypokalemia [extracellular K concentration ([K]o) changed from 5.4 to 2.7 mM]. E: reduction of inward-rectifier K current (IK1) by 30% (approximately the same reduction of IK1 as in D). F: 10-mV shift to more negative voltages of the steady-state inactivation curve [f∞ in the L-type Ca channel (LCC) model] to suppress window ICa,L.