TITLE Na persistent channel
: used in distal oblique dendrites to assist Ca spike initiation
:
: modified to use CVode Carl Gold 08/12/03
: Updated by YiotaPoirazi 26/1/05
NEURON {
SUFFIX nap
USEION na READ ena WRITE ina
RANGE gnabar,vhalf, K, ina
}
UNITS {
(mA) = (milliamp)
(mV) = (millivolt)
}
PARAMETER {
K = 4.5 (1) : slope of steady state variable
: gnabar = 0.001e2 (mho/cm2) : suggested conductance, 1 percent of the transient Na current
gnabar = 0 (mho/cm2)
vhalf = 50.4 (mV) : half potential
}
ASSIGNED {
v (mV)
ena (mV)
ina (mA/cm2)
n_inf
tau (ms)
}
STATE { n }
BREAKPOINT {
SOLVE states METHOD cnexp
ina = gnabar*n*n*n*(vena)
}
INITIAL {
rates(v)
n = n_inf
}
DERIVATIVE states {
rates(v)
n' = (n_infn)/tau
}
PROCEDURE rates(v(mV)) {
n_inf = 1 / (1 + (exp(vhalf  v)/K))
tau =1
}
