108 lines
1.5 KiB
Modula-2
108 lines
1.5 KiB
Modula-2
TITLE Na channels in VCN auditory neurons of guinea pig
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: na=gna*m^3*h
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: based on Rothman and Manis 2003
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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 na_VCN2003
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USEION na READ ena WRITE ina
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NONSPECIFIC_CURRENT il
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RANGE gnabar
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RANGE m_inf,h_inf
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RANGE tau_m,tau_h
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RANGE m_exp,h_exp
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RANGE ina,gna
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RANGE gl,el
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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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gnabar = 0.2 (mho/cm2)
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ena=55 (mV)
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gl= 4.0e-4 (mho/cm2)
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el=-57 (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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m h
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}
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ASSIGNED {
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gna (mho/cm2)
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ina (mA/cm2)
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il (mA/cm2)
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m_inf
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h_inf
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tau_m
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tau_h
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m_exp
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h_exp
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tadj3
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}
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BREAKPOINT {
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SOLVE states
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gna=gnabar * m*m*h
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ina = gna * (v - ena)
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il=gl*(v-el)
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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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m = m + m_exp * (m_inf - m)
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h = h + h_exp * (h_inf - h)
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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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tadj3 = 3.0 ^ ((celsius-22)/ 10 )
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evaluate_fct(v)
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m= m_inf
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h= h_inf
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}
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PROCEDURE evaluate_fct(v(mV)) {
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m_inf = 1 / (1+exp(-(v + 38) / 7))
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h_inf = 1 / (1+exp((v + 65) / 6))
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tau_m = (10 / (5*exp((v+60) / 18) + 36*exp(-(v+60) / 25))) + 0.04
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tau_h = (100 / (7*exp((v+60) / 11) + 10*exp(-(v+60) / 25))) + 0.6
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tau_m=tau_m/tadj3
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tau_h=tau_h/tadj3
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m_exp = 1 - exp(-dt/tau_m)
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h_exp = 1 - exp(-dt/tau_h)
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}
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UNITSON
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