Dissecting the roles of calcium cycling and its coupling with voltage in the genesis of early afterdepolarizations in cardiac myocyte models
Fig 4
EADs driven by Ca oscillations alone.
α(kmax) = 7, α(JCaslmyo) = 3.6, and α(INCX)=2.2. A. Phase diagram in the α(PCa) − α(GKs) plane. EADs occur in the magenta region. B. An example showing Vm, [Ca]sub, ICa,L, and INCX versus time from the EAD region [α(GKs) = 0.56, α(PCa)=2.8, marked as star in A]. The first two vertical dashed lines indicate the takeoff of the first two EADs and the third vertical dashed line marks the peak of the EAD prior to the last one. C. The same case as in B but [Ca]sub is clamped at two different levels in the plateau (grey patch in the [Ca]sub panel in B). D. The same case as in B but Vm is clamped at two different levels in the plateau (grey patch in the Vm panel in B). E. Upper panel: Vm and [Ca]sub versus time when ICa,L is clamped at a constant in the plateau (dashed line in the ICa,L panel in B). Lower panel: Vm and [Ca]sub versus time when INCX is clamped at a constant in the plateau (dashed line in the INCX panel in B).