TITLE Voltage-gated low threshold potassium current from Kv1 subunits
COMMENT
ENDCOMMENT
NEURON {
SUFFIX kv1
USEION k READ ek WRITE ik
RANGE gk, gbar, ik
GLOBAL ninf, taun
THREADSAFE
}
UNITS {
(mV) = (millivolt)
(mA) = (milliamp)
(nA) = (nanoamp)
(pA) = (picoamp)
(S) = (siemens)
(nS) = (nanosiemens)
(pS) = (picosiemens)
(um) = (micron)
(molar) = (1/liter)
(mM) = (millimolar)
}
CONSTANT {
q10 = 3
ca = 0.10 (1/ms) cva = 50 (mV)
cka = -33.90877 (mV)
cb = 0.12889 (1/ms)
cvb = 50 (mV)
ckb = 7.42101 (mV)
}
PARAMETER {
v (mV)
celsius (degC)
gbar = 10 (pS/um2)
}
ASSIGNED {
ik (mA/cm2)
ek (mV)
gk (mho/cm2)
ninf
taun (ms)
alphan (1/ms)
betan (1/ms)
qt
}
STATE { n }
INITIAL {
qt = q10^((celsius-22 (degC))/10 (degC))
rates(v)
n = ninf
}
BREAKPOINT {
SOLVE states METHOD cnexp
gk = gbar * n^4
ik = gk * (v - ek)*(1e-4)
}
DERIVATIVE states {
rates(v)
n' = (ninf-n)/taun
}
PROCEDURE rates(v (mV)) {
alphan = alphanfkt(v)
betan = betanfkt(v)
ninf = alphan/(alphan+betan)
taun = 1/(qt*(alphan + betan))
}
FUNCTION alphanfkt(v (mV)) (1/ms) {
alphanfkt = ca * exp(-(v+cva)/cka)
}
FUNCTION betanfkt(v (mV)) (1/ms) {
betanfkt = cb * exp(-(v+cvb)/ckb)
}