81 lines
1.1 KiB
Modula-2
81 lines
1.1 KiB
Modula-2
TITLE Ih channels in VCN auditory neurons
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: ih=ghmax*r*(v-eh)
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: based on Rothman and Manis (2003c)
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: Modifications by Yi Zhou for an MSO model
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INDEPENDENT {t FROM 0 TO 1 WITH 1 (ms)}
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NEURON {
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SUFFIX ih_VCN2003
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USEION h READ eh WRITE ih VALENCE 1
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RANGE ghbar
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RANGE r_inf,tau_r,r_exp
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RANGE ih,gh
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}
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UNITS {
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(mA) = (milliamp)
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(mV) = (millivolt)
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}
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PARAMETER {
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ghbar = 0.002 (mho/cm2)
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eh=-43 (mV)
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celsius =22 (degC)
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dt (ms)
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v (mV)
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}
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STATE {
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r
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}
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ASSIGNED {
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gh (mho/cm2)
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ih (mA/cm2)
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r_inf
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tau_r
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r_exp
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tadj
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}
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BREAKPOINT {
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SOLVE states
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gh=ghbar *r
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ih = gh*(v-eh)
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}
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PROCEDURE states() { : this discretized form is more stable
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evaluate_fct(v)
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r = r + r_exp * (r_inf - r)
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VERBATIM
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return 0;
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ENDVERBATIM
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}
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UNITSOFF
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INITIAL {
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:
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: Q10 was assumed to be 3 for both currents
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:
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tadj = 3.0 ^ ((celsius-22)/ 10 )
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evaluate_fct(v)
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r= r_inf
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}
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PROCEDURE evaluate_fct(v(mV)) {
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tau_r = (100000/(237*exp((v+60)/12)+17*exp(-(v+60)/14))+25)/ tadj
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r_inf = 1/(1+exp((v+76)/7))
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r_exp = 1 - exp(-dt/tau_r)
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}
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UNITSON
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