: $Id: H.mod,v 1.21 2010/02/19 17:15:36 billl Exp $
COMMENT
based on Otto Friesen Neurodynamix model
ENDCOMMENT
TITLE H channel
UNITS {
(mV) = (millivolt)
(mA) = (milliamp)
}
NEURON {
SUFFIX H
GLOBAL eh, VhlfMaxm, minf
USEION other WRITE iother VALENCE 1.0
RANGE i,g,gmax,slopem,taum
THREADSAFE
}
ASSIGNED {
i (mA/cm2)
v (mV)
g (mho/cm2)
minf
iother (mA/cm2)
}
STATE {
m
}
PARAMETER {
eh = -20 (mV)
gmax = 5e-07 (mho/cm2)
VhlfMaxm = -74
slopem = -10
taum = 50 (ms)
}
PROCEDURE iassign () {
i = g*(v-eh)
iother = i
}
BREAKPOINT {
SOLVE states METHOD cnexp
g = m * gmax
iassign()
}
INITIAL {
settables(v)
m = minf
g = m * gmax
iassign()
}
DERIVATIVE states {
settables(v)
m' = ( minf - m ) / taum
}
UNITSOFF
PROCEDURE settables(v (mV)) {
TABLE minf
FROM -200 TO 200 WITH 401
minf = 1 / (1 + exp((VhlfMaxm - v)/ slopem ) )
}
UNITSON