TITLE Ika CA1
UNITS {
(mA) = (milliamp)
(mV) = (millivolt)
}
NEURON {
SUFFIX kacurrent
NONSPECIFIC_CURRENT ika, ikad
RANGE g, gd, e, ika, ikad, ntau, ltau, ndtau, ninf, ndinf, linf
}
PARAMETER {
v (mV)
celsius (degC)
g= 0.048 (mho/cm2)
gd= 0 (mho/cm2)
e= 90 (mV)
}
STATE {
n
nd : distal
l
}
ASSIGNED {
ika (mA/cm2)
ikad (mA/cm2)
ninf
ntau (ms)
ndinf
ndtau (ms)
linf
ltau (ms)
}
BREAKPOINT {
SOLVE states METHOD cnexp
ika=g*n*l*(ve)
ikad=gd*nd*l*(ve)
}
DERIVATIVE states {
rates(v)
n'= (ninf n)/ ntau
l'= (linf l)/ ltau
nd'= (ndinfnd)/ndtau
}
INITIAL {
rates(v)
n= ninf
l= linf
}
PROCEDURE rates(v (mV)) {
LOCAL a, b
UNITSOFF
a = exp(0.038*(1.5+1/(1+exp(v+40)/5))*(v11))
b = exp(0.038*(0.825+1/(1+exp(v+40)/5))*(v11))
ntau=4*b/(1+a)
if (ntau<0.1) {ntau=0.1}
ninf=1/(1+a)
a=exp(0.038*(1.8+1/(1+exp(v+40)/5))*(v+1))
b=exp(0.038*(0.7+1/(1+exp(v+40)/5))*(v+1))
ndtau=2*b/(1+a)
if (ndtau<0.1) {ndtau=0.1}
ndinf=1/(1+a)
a = exp(0.11*(v+56))
ltau=0.26*(v+50)
if (ltau<2) {ltau=2}
linf=1/(1+a)
UNITSON
}
