UNITS {
(mA) = (milliamp)
(mV) = (millivolt)
(molar) = (1/liter)
(mM) = (millimolar)
F = 96485 (coul)
R = 8.3134 (joule/degC)
}
PARAMETER {
v (mV)
celsius (degC)
PcalBar=0.00006622 (cm/s)
ki=.00002 (mM)
cai=5.e-5 (mM)
cao = 10 (mM)
q10m=11.45
q10Ampl=2.1
}
NEURON {
SUFFIX CAl
USEION ca READ cai,cao WRITE ica
RANGE PcalBar
GLOBAL minf,taum
}
STATE {
m
}
ASSIGNED {
ica (mA/cm2)
Pcal (cm/s)
minf
taum
}
INITIAL {
rates(v)
m = minf
}
UNITSOFF
BREAKPOINT {
LOCAL qAmpl
qAmpl = q10Ampl^((celsius - 21)/10)
SOLVE states METHOD cnexp
Pcal = qAmpl*PcalBar*m*m*h2(cai)
ica = Pcal*ghk(v,cai,cao)
}
FUNCTION h2(cai(mM)) {
h2 = ki/(ki+cai)
}
FUNCTION ghk(v(mV), ci(mM), co(mM)) (mV) {
LOCAL a
a=2*F*v/(R*(celsius+273.15)*1000)
ghk=2*F/1000*(co - ci*exp(a))*func(a)
}
FUNCTION func(a) {
if (fabs(a) < 1e-4) {
func = -1 + a/2
}else{
func = a/(1-exp(a))
}
}
FUNCTION alpm(v(mV)) {
:TABLE FROM -150 TO 150 WITH 200
alpm = 0.1967*(-1.0*(v-15)+19.88)/(exp((-1.0*(v-15)+19.88)/10.0)-1.0)
}
FUNCTION betm(v(mV)) {
:TABLE FROM -150 TO 150 WITH 200
betm = 0.046*exp(-(v-15)/20.73)
}
DERIVATIVE states {
rates(v)
m' = (minf - m)/taum
}
PROCEDURE rates(v (mV)) { :callable from hoc
LOCAL a, qm
TABLE taum, minf FROM -150 TO 150 WITH 3000 :Mitti
qm = q10m^((celsius - 22)/10)
a = alpm(v)
taum = 1/((a + betm(v))*qm)
minf = 1/(1+exp(-(v+11)/5.7)) ^0.5
}
UNITSON