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: Comment: The persistent component of the K current
: Reference: Voltage-gated K+ channels in layer 5 neocortical pyramidal neurones from young rats:subtypes and gradients,Korngreen and Sakmann, J. Physiology, 2000
NEURON {
SUFFIX K_P
USEION k READ ek WRITE ik
RANGE gbar, g, ik
}
UNITS {
(S) = (siemens)
(mV) = (millivolt)
(mA) = (milliamp)
}
PARAMETER {
gbar = 0.00001 (S/cm2)
vshift = 0 (mV)
tauF = 1
}
ASSIGNED {
v (mV)
ek (mV)
ik (mA/cm2)
g (S/cm2)
celsius (degC)
mInf
mTau
hInf
hTau
}
STATE {
m
h
}
BREAKPOINT {
SOLVE states METHOD cnexp
g = gbar*m*m*h
ik = g*(v-ek)
}
DERIVATIVE states {
rates()
m' = (mInf-m)/mTau
h' = (hInf-h)/hTau
}
INITIAL{
rates()
m = mInf
h = hInf
}
PROCEDURE rates() {
LOCAL qt
qt = 2.3^((celsius-21)/10)
UNITSOFF
mInf = 1 / (1 + exp(-(v - (-14.3 + vshift)) / 14.6))
if (v < -50 + vshift){
mTau = tauF * (1.25+175.03*exp(-(v - vshift) * -0.026))/qt
} else {
mTau = tauF * (1.25+13*exp(-(v - vshift) * 0.026))/qt
}
hInf = 1/(1 + exp(-(v - (-54 + vshift))/-11))
hTau = (360+(1010+24*(v - (-55 + vshift)))*exp(-((v - (-75 + vshift))/48)^2))/qt
UNITSON
}
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