"nai is being written at the same location nadifl and Na_acc"
Is this message anything to worry about? Perhaps I could merge the 2 .mod files into a single .mod file? Looking at the equations, would this be possible? I would be so grateful for any advice. PLease find the 2 .mod files below.
1) Na_acc.mod
Code: Select all
TITLE Sodium ion accumulation
: Intracellular sodium ion accumulation
NEURON {
SUFFIX Na_acc
USEION na READ ina,nai WRITE nai
RANGE Vi, Naneutral : electroneutral sodium accumulation
}
UNITS {
(mV) = (millivolt)
(um) = (micron)
(mM) = (milli/liter)
(mA) = (milliamp)
F = (faraday) (coulombs)
}
PARAMETER {
Naneutral = 3e-5 (mA/cm2) <0,1e6>
Vi = 13668e-12 (cm3)
ina (mA/cm2)
}
STATE {
nai START 9.19 (mM)
}
LOCAL ViF
INITIAL {
VERBATIM
nai = _ion_nai;
ENDVERBATIM
ViF = F*Vi*2e4
}
BREAKPOINT {
SOLVE state METHOD derivimplicit
}
DERIVATIVE state {
nai' = -(ina-Naneutral)/(ViF)
}
2) nadifl.mod
Code: Select all
COMMENT
Longitudinal diffusion of sodium (no buffering)
(equivalent modified euler with standard method and
equivalent to diagonalized linear solver with CVODE )
ENDCOMMENT
NEURON {
SUFFIX nadifl
USEION na READ ina WRITE nai
RANGE D
}
UNITS {
(mM) = (milli/liter)
(um) = (micron)
FARADAY = (faraday) (coulomb)
PI = (pi) (1)
}
PARAMETER {
D = .6 (um2/ms)
}
ASSIGNED {
ina (milliamp/cm2)
diam (um)
}
STATE {
nai (mM)
}
BREAKPOINT {
SOLVE conc METHOD sparse
}
KINETIC conc {
COMPARTMENT PI*diam*diam/4 {nai}
LONGITUDINAL_DIFFUSION D {nai}
~ nai << (-ina/(FARADAY)*PI*diam*(1e4))
}