TITLE Motoneuron HVA L-type Calcium channels : : The parameters for this current come from V. Booth et al. J Neurophysiol 78:3371-3385, 1997 : Iterative equations : I shifted the activation of this current to the same range as N_Ca.mod : NEURON { SUFFIX L_HVA_Ca USEION ca READ eca WRITE ica RANGE gcabar RANGE m_inf } UNITS { (mA) = (milliamp) (mV) = (millivolt) } PARAMETER { gcabar = 0.0003 (mho/cm2) :original = 7e-05 eca = 80 (mV) : celcius = 36 (degC) dt (ms) tau_m = 20 (ms) v (mV) theta_m = -10 (mV) kappa_m = -6 (mV) :original = -7 } STATE { m } ASSIGNED { ica (mA/cm2) m_inf tadj } BREAKPOINT { SOLVE states METHOD cnexp ica = gcabar * m * (v - eca) :I have tried this as m*m also } DERIVATIVE states { evaluate_fct(v) m' = (m_inf - m) / tau_m } UNITSOFF INITIAL { : : Q10 was assumed to be 3 for both currents : : tadj = 3.0 ^ ((celsius-36)/ 10 ) evaluate_fct(v) m = m_inf } PROCEDURE evaluate_fct(v(mV)) { m_inf = 1 / (1 + (Exp((v - theta_m)/ kappa_m))): / tadj } FUNCTION vtrap(x,y) { if (fabs(x/y) < 1e-6) { vtrap = y*(1 - x/y/2) }else{ vtrap = x/(Exp(x/y)-1) } } FUNCTION Exp(x) { if (x < -100) { Exp = 0 }else{ Exp = exp(x) } }