TITLE Sodium persistent current for RD Traub, J Neurophysiol 89:909-921, 2003 COMMENT Implemented by Maciej Lazarewicz 2003 (mlazarew@seas.upenn.edu) ENDCOMMENT INDEPENDENT { t FROM 0 TO 1 WITH 1 (ms) } UNITS { (mV) = (millivolt) (mA) = (milliamp) } NEURON { SUFFIX nap USEION na READ ena WRITE ina RANGE gbar, ina, m } PARAMETER { gbar = 0.0 (mho/cm2) v (mV) ena (mV) } ASSIGNED { ina (mA/cm2) minf (1) mtau (ms) } STATE { m } BREAKPOINT { SOLVE states METHOD cnexp ina = gbar * m * ( v - ena ) } INITIAL { settables(v) m = minf m = 0 } DERIVATIVE states { settables(v) m' = ( minf - m ) / mtau } UNITSOFF PROCEDURE settables(v (mV)) { TABLE minf, mtau FROM -120 TO 40 WITH 641 minf = 1 / ( 1 + exp( ( - v - 48 ) / 10 ) ) if( v < -40.0 ) { mtau = 0.025 + 0.14 * exp( ( v + 40 ) / 10 ) }else{ mtau = 0.02 + 0.145 * exp( ( - v - 40 ) / 10 ) } } UNITSON