TITLE Basic sodium current
 
COMMENT
 from "Gamma Oscillation by Synaptic Inhibition in a Hippocampal Interneuronal Network Model" (Wang and Buzsaki 1996)
 Used in Role of a Striatal Slowly Inactivating Potassion Current in Short-term Facilitation of Corticostriatal Inputs" A computer Simulation Study" (Mahon et al. 2000)
Implemented by Kevin M. Biddell kevin.biddell@gmail.com
7/11/06

NOTE: 1S=1mho Neuron wants the units in mhos not millisiemens, please note the conversion!

Phi =5 and no q10 or temp adjustment according to Bruno Delord 11/13/06

ENDCOMMENT
 
UNITS {
        (mA) = (milliamp)
        (mV) = (millivolt)
	
}
 
NEURON {
 	SUFFIX Nam
	USEION na WRITE ina
	RANGE gnabar, gna, minf, hinf, ah, Bh
}
 
INDEPENDENT {t FROM 0 TO 1 WITH 1 (ms)}
 
PARAMETER {
  	
	ena	= 55	(mV)
	gnabar	= 0.035 (mho/cm2) : 35mS
	phi	= 5 < 0, 1e9 > : from delord 11/13/06 
	Vam	= -28 :NOT the original value from wang and Buzsaki
	Kam	= 1
	Vbm	= -53 :NOT the original value from wang and Buzsaki
	Kbm	= 18
	Vah	= -51 :NOT the original value from wang and Buzsaki
	Kah	= 20
	Vbh	= -21 :NOT the original value from wang and Buzsaki
	Kbh	= 1
	       
}
 
STATE {
        m h
}
 
ASSIGNED {
        v  (mV)
	ina (mA/cm2)
	celsius		(degC)
 	minf
	hinf
	ah
	Bh
        gna
}
 
BREAKPOINT {
        SOLVE states METHOD cnexp
        gna = gnabar*m^3*h
        ina = gna*(v - ena)
  
}
 
UNITSOFF
 
INITIAL {
	rates(v)
	m = minf
	h= hinf
}

DERIVATIVE states {  :Computes states variable m and h
        rates(v)      :             at the current v and dt.
       
	h'=phi*(ah*(1-h)-Bh*h)

}
 
PROCEDURE rates(v) {  :Computes rate and other constants at current v.
                      :Call once from HOC to initialize inf at resting v.
        LOCAL  am, Bm
        
        
	am = (-0.1*(v-Vam)/Kam/(exp(-0.1*(v-Vam)/Kam)-1))
        Bm = 4*exp(-(v-Vbm)/Kbm)
        ah = 0.07*exp(-(v-Vah)/Kah)
        Bh=  1/(1+exp(-0.1*(v-Vbh)/Kbh))
        minf = am/(am+Bm)
 	hinf = ah/(ah+Bh)
	m=minf      
}
 
UNITSON