FIGURE 9.

Comparison between solutions when solving the model equations explicitly and implicitly, where the fast buffering approximation is used to model the endogenous buffering. The nonbuffering SERCA pump has been used here. (A) The difference between the sum of the cytosolic, ER and buffered calcium, and the input into the cell from the cell exterior. This quantity should be conserved. We give the results when the implicit equations are used and when the explicit equations are used. (B) Cytosolic calcium oscillations. The results from the implicit and explicit equations are plotted on the same axes, but are indistinguishable. (C) The difference between the cytosolic calcium concentrations when using the implicit and explicit equations.