Fig 4. Dynamics of the model featuring the Ca_V+BK module.

The state space is {S, R_F, R_H, R_L, G, $f_{\text{kn}}^o$, $f_{\text{hc}}^o$, V, $f_{\text{cv}}^o$, $f_{\text{cv}}^c$, $f_{\text{bk}}^o$, C}. As in Fig 2, the initial stimulus is S(0) = 25 nM is used. From top to bottom, the numerical solutions obtained with the parameters listed in Table 2 are shown for: [Ca²⁺]_i (C) together with cGMP concentration (G), open channel fractions, ionic currents and membrane potential. The ionic currents are displayed in current densities (left axis) and as current normalised by capacitance (right axis).