Model is underconstrained.
The following variables couldn't be defined:
 * Vm in component membrane
 * C in component membrane
 * i_K in component potassium_current
 * i_R in component repolarising_current
 * Jcat in component Jcat
 * PoBKCa in component potassium_current
 * PoSKCa in component potassium_current
 * d/dt Vm in component membrane
 * d/dt IP3 in component IP3
 * d/dt Ca in component Ca