TITLE Cerebellum Granule Cell Model COMMENT KM channel Author: A. Fontana CoAuthor: T.Nieus Last revised: 20.11.99 ENDCOMMENT NEURON { SUFFIX GRC_KM USEION k READ ek WRITE ik RANGE gkbar, ik, g, alpha_n, beta_n RANGE Aalpha_n, Kalpha_n, V0alpha_n RANGE Abeta_n, Kbeta_n, V0beta_n RANGE V0_ninf, B_ninf RANGE n_inf, tau_n } UNITS { (mA) = (milliamp) (mV) = (millivolt) } PARAMETER { Aalpha_n = 0.0033 (/ms) Kalpha_n = 40 (mV) V0alpha_n = -30 (mV) Abeta_n = 0.0033 (/ms) Kbeta_n = -20 (mV) V0beta_n = -30 (mV) V0_ninf = -35 (mV) :-30 B_ninf = 6 (mV) :6:4 rimesso a 6 dopo calibrazione febbraio 2003 v (mV) gkbar= 0.00025 (mho/cm2) :0.0001 ek = -84.69 (mV) celsius = 30 (degC) } STATE { n } ASSIGNED { ik (mA/cm2) n_inf tau_n (ms) g (mho/cm2) alpha_n (/ms) beta_n (/ms) } INITIAL { rate(v) n = n_inf } BREAKPOINT { SOLVE states METHOD derivimplicit g = gkbar*n ik = g*(v - ek) alpha_n = alp_n(v) beta_n = bet_n(v) } DERIVATIVE states { rate(v) n' =(n_inf - n)/tau_n } FUNCTION alp_n(v(mV))(/ms) { LOCAL Q10 Q10 = 3^((celsius-22(degC))/10(degC)) alp_n = Q10*Aalpha_n*exp((v-V0alpha_n)/Kalpha_n) } FUNCTION bet_n(v(mV))(/ms) { LOCAL Q10 Q10 = 3^((celsius-22(degC))/10(degC)) bet_n = Q10*Abeta_n*exp((v-V0beta_n)/Kbeta_n) } PROCEDURE rate(v (mV)) {LOCAL a_n, b_n TABLE n_inf, tau_n DEPEND Aalpha_n, Kalpha_n, V0alpha_n, Abeta_n, Kbeta_n, V0beta_n, V0_ninf, B_ninf, celsius FROM -100 TO 30 WITH 13000 a_n = alp_n(v) b_n = bet_n(v) tau_n = 1/(a_n + b_n) : n_inf = a_n/(a_n + b_n) n_inf = 1/(1+exp(-(v-V0_ninf)/B_ninf)) }