Model is underconstrained.
The following variables couldn't be defined:
 * V in component membrane
 * i_CaT in component T_type_calcium_channel_current
 * i_CaL in component L_type_calcium_channel_current
 * i_K_DR in component voltage_sensitive_potassium_current
 * i_K_Ca in component calcium_activated_potassium_current
 * i_Leak in component leak_current
 * E_Ca in component reversal_potentials
 * E_K in component reversal_potentials
 * Cai in component intracellular_calcium_concentration
 * m_infinity in component L_type_calcium_channel_current_m_gate
 * tau_m in component L_type_calcium_channel_current_m_gate
 * m_infinity in component T_type_calcium_channel_current_m_gate
 * tau_m in component T_type_calcium_channel_current_m_gate
 * h_infinity in component T_type_calcium_channel_current_h_gate
 * n_infinity in component voltage_sensitive_potassium_current_n_gate
 * j_exch in component intracellular_calcium_dynamics
 * j_in in component intracellular_calcium_dynamics
 * j_eff in component intracellular_calcium_dynamics
 * d/dt V in component membrane
 * d/dt m in component L_type_calcium_channel_current_m_gate
 * d/dt m in component T_type_calcium_channel_current_m_gate
 * d/dt h in component T_type_calcium_channel_current_h_gate
 * d/dt n in component voltage_sensitive_potassium_current_n_gate