COMMENT T-type Ca channel ca.mod to lead to thalamic ca current inspired by destexhe and huguenrd Uses fixed eca instead of GHK eqn changed from (AS Oct0899) changed for use with Ri18 (B.Kampa 2005) added DERIVATIVE block for use with cvode (C.Acker 2008) ENDCOMMENT INDEPENDENT {t FROM 0 TO 1 WITH 1 (ms)} NEURON { SUFFIX it USEION ca READ eca WRITE ica RANGE m, h, gca, gbar RANGE minf, hinf, mtau, htau, inactF, actF GLOBAL vshift,vmin,vmax, v12m, v12h, vwm, vwh, am, ah, vm1, vm2, vh1, vh2, wm1, wm2, wh1, wh2 } PARAMETER { gbar = 0.0008 (mho/cm2) : 0.12 mho/cm2 vshift = 0 (mV) : voltage shift (affects all) cao = 2.5 (mM) : external ca concentration cai (mM) v (mV) dt (ms) celsius (degC) vmin = -120 (mV) vmax = 100 (mV) v12m=50 (mV) v12h=78 (mV) vwm =7.4 (mV) vwh=5.0 (mV) am=3 (mV) ah=85 (mV) vm1=25 (mV) vm2=100 (mV) vh1=46 (mV) vh2=405 (mV) wm1=20 (mV) wm2=15 (mV) wh1=4 (mV) wh2=50 (mV) } UNITS { (mA) = (milliamp) (mV) = (millivolt) (pS) = (picosiemens) (um) = (micron) FARADAY = (faraday) (coulomb) R = (k-mole) (joule/degC) PI = (pi) (1) } ASSIGNED { ica (mA/cm2) gca (pS/um2) eca (mV) minf hinf mtau (ms) htau (ms) tadj } STATE { m h } INITIAL { trates(v+vshift) m = minf h = hinf } BREAKPOINT { SOLVE states METHOD cnexp gca = gbar*m*m*h ica = gca * (v - eca) } DERIVATIVE states { trates(v+vshift) m' = (minf-m)/mtau h' = (hinf-h)/htau } PROCEDURE trates(v) { TABLE minf, hinf, mtau, htau FROM vmin TO vmax WITH 199 rates(v): not consistently executed from here if usetable == 1 } PROCEDURE rates(v_) { LOCAL a, b minf = 1.0 / ( 1 + exp(-(v_+v12m)/vwm) ) hinf = 1.0 / ( 1 + exp((v_+v12h)/vwh) ) mtau = ( am + 1.0 / ( exp((v_+vm1)/wm1) + exp(-(v_+vm2)/wm2) ) ) htau = ( ah + 1.0 / ( exp((v_+vh1)/wh1) + exp(-(v_+vh2)/wh2) ) ) }