Model is underconstrained.
The following variables couldn't be defined:
 * V in component membrane
 * i_Ca in component calcium_current
 * i_K in component delayed_rectifier_potassium_current
 * i_K_Ca in component calcium_dependent_potassium_current
 * i_K_ATP in component nucleotide_sensitive_potassium_current
 * m_infinity in component calcium_current_m_gate
 * n_infinity in component delayed_rectifier_potassium_current_n_gate
 * omega in component calcium_dependent_potassium_current_omega_gate
 * a_infinity in component nucleotide_sensitive_potassium_current_a_gate
 * Jmem in component calcium_flux_through_the_membrane
 * Jer in component net_calcium_efflux_out_of_the_ER
 * J_SERCA in component calcium_influx_into_the_ER
 * Jleak in component calcium_leak_out_of_the_ER
 * JIP3 in component calcium_efflux_through_the_IP3R
 * O_infinity in component calcium_efflux_through_the_IP3R
 * IP3 in component calcium_efflux_through_the_IP3R
 * d/dt V in component membrane
 * d/dt n in component delayed_rectifier_potassium_current_n_gate
 * d/dt a in component nucleotide_sensitive_potassium_current_a_gate
 * d/dt c in component cytosolic_free_calcium_concentration
 * d/dt c_er in component ER_calcium_concentration