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: Comment: LVA ca channel. Note: mtau is an approximation from the plots
: Reference: Avery and Johnston 1996, tau from Randall 1997
: Comment: shifted by -10 mv to correct for junction potential
: Comment: corrected rates using q10 = 2.3, target temperature 34, orginal 21
NEURON {
SUFFIX Ca_LVA
USEION ca READ eca WRITE ica
RANGE gbar, g, ica
}
UNITS {
(S) = (siemens)
(mV) = (millivolt)
(mA) = (milliamp)
}
PARAMETER {
gbar = 0.00001 (S/cm2)
}
ASSIGNED {
v (mV)
eca (mV)
ica (mA/cm2)
g (S/cm2)
celsius (degC)
mInf
mTau
hInf
hTau
}
STATE {
m
h
}
BREAKPOINT {
SOLVE states METHOD cnexp
g = gbar*m*m*h
ica = g*(v-eca)
}
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
v = v + 10
mInf = 1.0000/(1+ exp((v - -30.000)/-6))
mTau = (5.0000 + 20.0000/(1+exp((v - -25.000)/5)))/qt
hInf = 1.0000/(1+ exp((v - -80.000)/6.4))
hTau = (20.0000 + 50.0000/(1+exp((v - -40.000)/7)))/qt
v = v - 10
UNITSON
}
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