This channel compiles properly before being edited with equations from Le Franc & Le Masson (2010) but

when inserted into the cell the error 'ca_ion mechanism not inserted in the soma' occurs. How do I rectify this? With an intracellular ca mechanism?

The following code:

Code: Select all

```
TITLE (L-type LVA calcium current)
INDEPENDENT {t FROM 0 TO 1 WITH 1 (ms)}
NEURON {
SUFFIX CaL13t
: USEION ca READ cai,cao
: USEION ca WRITE ica VALENCE 2
USEION ca READ cai, cao WRITE ica VALENCE 2
RANGE minf, mtau, hinf, htau, ica, pmax
GLOBAL m_vh
}
UNITS {
(mA) = (milliamp)
(mV) = (millivolt)
(mM) = (milli/liter)
FARADAY = 96489 (coul)
R = 8.314 (volt-coul/degC)
}
PARAMETER {
v (mV)
celsius (degC)
: cai (mM)
: cao (mM)
cai (mM)
cao (mM)
pmax = 4.25e-7 (cm/s)
m_vh = -33 (mV)
}
STATE {
m
h
}
ASSIGNED {
ica (mA/cm2)
mtau (ms)
minf
hinf
htau (ms)
}
BREAKPOINT {
SOLVE state METHOD cnexp
ica = pmax*m*m*h*ghk(v,cai,cao,2)
: ica = pmax*m*m*h*ghk(v,0.001,cao,2)
}
DERIVATIVE state {
rates(v)
m'= (minf-m) / mtau
h'= (hinf-h) / htau
}
INITIAL {
rates(v)
m = minf
h = hinf
}
FUNCTION ghk( v(mV), ci(mM), co(mM), z) (millicoul/cm3) {
LOCAL e, w
w = v * (.001) * z*FARADAY / (R*(celsius+273.16))
if (fabs(w)>1e-4)
{ e = w / (1-exp(-w)) }
else : denominator is small -> Taylor series
{ e = 1/(1-exp(-w)) }
ghk = - (pmax) * z*FARADAY * (co-ci*exp(-w)) * e
}
UNITSOFF
PROCEDURE rates(v(mV)) {
LOCAL m_alpha, m_beta
m_alpha = (0.1*(25-v))
m_beta = (1.0029/
(1+exp[(14.3907 - v)/3.1029])^0.5289)
mtau = 1/(m_alpha/(exp[m_alpha]))+[4*exp(-v/18)])
minf = -0.0012+m_beta
htau = 1500
hinf = 1 / (1+exp((v-14)/4.03))
}
UNITSON
```