TITLE slowly activating potassium current (M-current) COMMENT ********************************************* reference: Yamada, Koch & Adams (1989) Methods in Neuronal Modeling, MIT press found in: bullfrog sympathetic ganglion cells ********************************************* Assembled for MyFirstNEURON by Arthur Houweling ENDCOMMENT INDEPENDENT {t FROM 0 TO 1 WITH 1 (ms)} NEURON { SUFFIX iM USEION k READ ek WRITE ik RANGE gkbar, m_inf, tau_m, ik } UNITS { (mA) = (milliamp) (mV) = (millivolt) } PARAMETER { v (mV) celsius (degC) dt (ms) ek (mV) gkbar= 0.00031 (mho/cm2) : gkbar= 0.0006 (mho/cm2) } STATE { m } ASSIGNED { ik (mA/cm2) m_inf tau_m (ms) tau_h (ms) tadj } BREAKPOINT { SOLVE states :METHOD euler : ik = gkbar * m * (v-ek) ik = gkbar * m * (v+105) } :DERIVATIVE states { : evaluate_fct(v) : : m'= (m_inf-m) / tau_m :} PROCEDURE states() { evaluate_fct(v) m= m + (1-exp(-dt/tau_m))*(m_inf-m) } UNITSOFF INITIAL { : tadj = 2.3^((celsius-23)/10) tadj = 3^((celsius-23.5)/10) evaluate_fct(v) m = m_inf } PROCEDURE evaluate_fct(v(mV)) { LOCAL a,b tau_m = 1000.0/(3.3*(exp((v+35)/20)+exp(-(v+35)/20))) / tadj m_inf = 1.0 / (1+exp(-(v+35)/10)) } UNITSON