96 lines
1.3 KiB
Modula-2
96 lines
1.3 KiB
Modula-2
TITLE high threshold potassium channels in VCN auditory neurons
|
|
|
|
: k_HT=ght*(rr*n^2+(1-rr)*p)*(v-Ek)
|
|
: based on Rothman and Manis (2003c)
|
|
:
|
|
: Modifications by Yi Zhou for an MSO model
|
|
|
|
INDEPENDENT {t FROM 0 TO 1 WITH 1 (ms)}
|
|
|
|
NEURON {
|
|
SUFFIX kHT_VCN2003
|
|
USEION k READ ek WRITE ik
|
|
RANGE gkbar
|
|
RANGE n_inf,p_inf
|
|
RANGE tau_n,tau_p
|
|
RANGE n_exp,p_exp
|
|
RANGE ik,gk
|
|
|
|
}
|
|
|
|
|
|
UNITS {
|
|
(mA) = (milliamp)
|
|
(mV) = (millivolt)
|
|
}
|
|
|
|
PARAMETER {
|
|
gkbar = 0.03 (mho/cm2)
|
|
ek=-70 (mV)
|
|
celsius =22 (degC)
|
|
dt (ms)
|
|
v (mV)
|
|
|
|
}
|
|
|
|
STATE {
|
|
n p rr
|
|
}
|
|
|
|
ASSIGNED {
|
|
gk(mho/cm2)
|
|
ik (mA/cm2)
|
|
n_inf
|
|
p_inf
|
|
tau_n
|
|
tau_p
|
|
n_exp
|
|
p_exp
|
|
tadj
|
|
}
|
|
|
|
|
|
BREAKPOINT {
|
|
SOLVE states
|
|
gk=gkbar *(rr*n^2+(1-rr)*p)
|
|
ik = gk*(v-ek)
|
|
}
|
|
|
|
|
|
|
|
PROCEDURE states() { : this discretized form is more stable
|
|
evaluate_fct(v)
|
|
n = n + n_exp * (n_inf - n)
|
|
p = p + p_exp * (p_inf - p)
|
|
VERBATIM
|
|
return 0;
|
|
ENDVERBATIM
|
|
}
|
|
|
|
UNITSOFF
|
|
INITIAL {
|
|
:
|
|
: Q10 was assumed to be 3 for both currents
|
|
:
|
|
tadj = 3.0 ^ ((celsius-22)/ 10 )
|
|
evaluate_fct(v)
|
|
n= n_inf
|
|
p= p_inf
|
|
rr=0.85
|
|
}
|
|
|
|
PROCEDURE evaluate_fct(v(mV)) {
|
|
|
|
tau_n = (100/(11*exp((v+60)/24)+21*exp(-(v+60)/23))+0.7)/ tadj
|
|
n_inf = 1/(1+exp(-(v+15)/5))^2
|
|
|
|
tau_p = (100/(4*exp((v+60)/32)+5*exp(-(v+60)/22))+5)/ tadj
|
|
p_inf = 1/(1+exp(-(v+23)/6))
|
|
|
|
n_exp = 1 - exp(-dt/tau_n)
|
|
p_exp = 1 - exp(-dt/tau_p)
|
|
|
|
}
|
|
|
|
UNITSON
|