FIGURE 5.

Deterministic simulation of steady-state bursting in the presence of glucose showing the three Ca²⁺ compartments (Eqs. 1–6, Methods). Parameters are as in Fig. 2 except g_KATP, which is 60 pS throughout, and k_PMCA, which is 0.18 ms⁻¹. (A) Membrane potential. (B) Weighted average of [Ca²⁺]_i and [Ca²⁺]_SS, corresponding to measured cytosolic [Ca²⁺], which declines throughout the active phase. (C) Subspace [Ca²⁺], which rises throughout active phase and activates K_slow to terminate the burst. (D) Store [Ca²⁺], which rises slowly in active phase and falls slowly in silent phase.