TITLE Transient Outward K+ current
COMMENT
modified From DiFrancesco & Noble 1985 Phil Trans R Soc Lond 307:353-398
modified for Neuron by FE GANNIER
francois.gannier@univ-tours.fr (University of TOURS)
ENDCOMMENT
INCLUDE "Unit.inc"
INCLUDE "Volume.inc"
NEURON {
SUFFIX ito
USEION k READ ek, ko, ki WRITE ik
USEION ca READ cai
RANGE g, ik, minf, mtau
}
PARAMETER {
Kmca = 0.0005 (mM)
Kmto = 10 (mM)
g = 0.28 (uS/mM)
: kb = 4 (mM)
}
STATE { : r
m
}
ASSIGNED {
v (mV)
celsius (degC) : 37
ik (mA/cm2)
minf
mtau (ms)
ek (mV)
ko (mM)
ki (mM)
cai (mM)
}
LOCAL RT
INITIAL {
RT = (1000)*R*(273.15+celsius)
rate(v)
m = minf
}
BREAKPOINT {
SOLVE states METHOD derivimplicit
: original
: ik = m * g/S * ((0.2 + ko) / (Km1 + ko)) * (cai / (Kmto + cai)) * ((v + 10) / (1 - exp(-0.2(/mV) * (v + 10)))) * (ki*exp(0.02(/mV) * v) - kb*exp(-0.02(/mV) * v))
: correction
ik = (1e-06)* m * g/S * (0.2 + (ko / (Kmto + ko))) * (cai / (Kmca + cai)) * (v + 10) / (1 - exp(-0.2(/mV) * (v + 10))) * (ki*exp(0.5 * v *F/RT) - ko*exp(-0.5 * v*F/RT))
}
DERIVATIVE states {
rate(v)
m' = (minf - m)/mtau
}
FUNCTION alp(v(mV)) (/ms) {
alp = (0.001)* 0.033(/s)*exp(-v / 17(mV))
}
FUNCTION bet(v(mV)) (/ms) {
bet = (0.001)* 33(/s) / (1 + exp(-(v + 10 (mV))/8(mV)))
}
: UNITSOFF
PROCEDURE rate(v(mV)) { LOCAL a, b
TABLE minf, mtau FROM -100 TO 100 WITH 200
a = alp(v) b = bet(v)
mtau = 1/(a + b)
minf = a * mtau
}
: UNITSON