TITLE
COMMENT
ENDCOMMENT
NEURON {
POINT_PROCESS GRANULE_Ampa_det_vi
NONSPECIFIC_CURRENT i
RANGE Q10_diff,Q10_channel
RANGE R, g, ic,yuno
RANGE Cdur, Erev
RANGE r1FIX, r2, r3,r4,r5,gmax,r1,r6,r6FIX,kB
RANGE tau_1, tau_rec, tau_facil, U
RANGE PRE,T,Tmax
RANGE diffuse,Trelease,lamd
RANGE M,Diff,Rd,O
RANGE tspike
RANGE nd, syntype, gmax_factor
}
UNITS {
(nA) = (nanoamp)
(mV) = (millivolt)
(umho) = (micromho)
(mM) = (milli/liter)
(pS) = (picosiemens)
(nS) = (nanosiemens)
(um) = (micrometer)
PI = (pi) (1)
}
PARAMETER {
syntype
gmax_factor = 1
Q10_diff = 1.5
Q10_channel = 2.4
: Parametri Postsinaptici
gmax = 1200 (pS)
U = 0.42 (1) < 0, 1 >
tau_rec = 8 (ms) < 1e-9, 1e9 >
tau_facil = 5 (ms) < 0, 1e9 >
M = 21.515 : numero di (kilo) molecole in una vescicola
Rd = 1.03 (um)
Diff = 0.223 (um2/ms)
Cdur = 0.3 (ms)
r1FIX = 5.4 (/ms/mM)
r2 = 0.82 (/ms)
r3 = 0 (/ms)
r4 = 0 (/ms)
r5 = 0.013 (/ms)
r6FIX = 1.12 (/ms/mM)
Erev = 0 (mV)
kB = 0.44 (mM)
: Parametri Presinaptici
tau_1 = 1 (ms) < 1e-9, 1e9 >
u0 = 0 (1) < 0, 1 > : se u0=0 al primo colpo y=U
Tmax = 1 (mM)
: Diffusion
diffuse = 1
lamd = 20 (nm)
nd = 1
celsius (degC)
}
ASSIGNED {
v (mV) : postsynaptic voltage
i (nA) : current = g*(v - Erev)
ic (nA) : current = g*(v - Erev)
g (pS) : conductance
r1 (/ms)
r6 (/ms)
T (mM)
Trelease (mM)
tspike[100] (ms)
x
tsyn (ms)
PRE[100]
Mres (mM)
numpulses
tzero
gbar_Q10 (mho/cm2)
Q10 (1)
yuno
}
STATE {
C
O
D
}
INITIAL {
C=1
O=0
D=0
T=0 (mM)
yuno = 0
numpulses=0
Trelease=0 (mM)
tspike[0]=1e12 (ms)
gbar_Q10 = Q10_diff^((celsius-30)/10)
Q10 = Q10_channel^((celsius-30)/10)
: fattore di conversione che comprende molecole -> mM
: n molecole/(Na*V) -> M/(6.022e23*1dm^3)
Mres = 1e3 * ( 1e3 * 1e15 / 6.022e23 * M ) : (M) to (mM) so 1e3, 1um^3=1dm^3*1e-15 so 1e15
numpulses=0
FROM i=1 TO 100 { PRE[i-1]=0 tspike[i-1]=0 }
tspike[0]=1e12 (ms)
if(tau_1>=tau_rec){
printf("Warning: tau_1 (%g) should never be higher neither equal to tau_rec (%g)!\n",tau_1,tau_rec)
tau_rec=tau_1+1e-5
}
}
FUNCTION imax(a,b) {
if (a>b) { imax=a }
else { imax=b }
}
FUNCTION diffusione(){
LOCAL DifWave,i,cntc,fi
DifWave=0
cntc=imax(numpulses-100,0)
FROM i=cntc TO numpulses{
:printf ("%g %g ",numpulses,fmod(numpulses,10))
fi=fmod(i,100)
:printf ("%g %g %g __ ",i,numpulses,fi)
tzero=tspike[fi]
if(t>tzero){
DifWave=DifWave+PRE[fi]*Mres*exp(-Rd*Rd/(4*Diff*(t-tzero)))/((4*PI*Diff*(1e-3)*lamd)*(t-tzero))^nd
}
}
:printf("\n\n")
diffusione=DifWave
}
BREAKPOINT {
if ( diffuse && (t>tspike[0]) ) { Trelease= T + diffusione() } else { Trelease=T }
SOLVE kstates METHOD sparse
g = gmax * gbar_Q10 * O
i = (1e-6) * g * (v - Erev) * gmax_factor
ic = i
}
KINETIC kstates {
r1 = r1FIX * Trelease^2 / (Trelease + kB)^2
r6 = r6FIX * Trelease^2 / (Trelease + kB)^2
~ C <-> O (r1*Q10,r2*Q10)
:~ O <-> D (r3*Q10,r4*Q10)
~ D <-> C (r5*Q10,r6*Q10)
CONSERVE C+O+D = 1
}
NET_RECEIVE(weight, on, nspike, tzero (ms),y, z, u, tsyn (ms)) {LOCAL fi
: *********** ATTENZIONE! ***********
:
: Qualora si vogliano utilizzare impulsi di glutammato saturanti e'
: necessario che il pulse sia piu' corto dell'intera simulazione
: altrimenti la variabile on non torna al suo valore di default.
INITIAL {
y = 0
z = 0
u = u0
tsyn = t
nspike = 1
}
if (flag == 0) {
: Qui faccio rientrare la modulazione presinaptica
nspike = nspike + 1
if (!on) {
tzero = t
on = 1
z = z*exp( - (t - tsyn) / (tau_rec) )
z = z + ( y*(exp(-(t - tsyn)/tau_1) - exp(-(t - tsyn)/(tau_rec)))/((tau_1/(tau_rec))-1) )
y = y*exp(-(t - tsyn)/tau_1)
x = 1-y-z
if (tau_facil > 0) {
u = u*exp(-(t - tsyn)/tau_facil)
u = u + U * ( 1 - u )
} else { u = U }
y = y + x * u
T=Tmax*y
yuno = y
fi=fmod(numpulses,100)
PRE[fi]=y : PRE[numpulses]=y
:PRE=1 : Istruzione non necessaria ma se ommesso allora le copie dell'oggetto successive alla prima non funzionano!
:}
: all'inizio numpulses=0 !
tspike[fi] = t
numpulses=numpulses+1
tsyn = t
}
net_send(Cdur, nspike)
}
if (flag == nspike) {
tzero = t
T = 0
on = 0
}
}