: Rod Photoreceptor Kv channel

NEURON 
{
	SUFFIX Kv
	
	USEION Kv WRITE iKv VALENCE 1
	
	
        RANGE gKv,gKvbar, eKv
	
	
	
	

}

UNITS
{
	(mA) = (milliamp)
	(mV) = (millivolt)
	(mS) = (millimho)
	
}

PARAMETER
{
        : potassium rectifier
        gKvbar = 2.0 (mS/cm2) <0,1e9>
        eKv = -80 (mV)
       
        

}

STATE
{
	mKv
	hKv
	
}

ASSIGNED
{
	v (mV)
	
	iKv (mA/cm2)
              
          : potussium rectifier, K
	infmKv
	taumKv  (ms)
	infhKv
	tauhKv  (ms)
           
     
	gKv (mho/cm2)
	
}

INITIAL
{
	rate(v)
	mKv = infmKv
	hKv  = infhKv
}




BREAKPOINT
{
	SOLVE states METHOD cnexp
	gKv = (0.001)*gKvbar*mKv*mKv*mKv *hKv
	iKv = gKv*(v - eKv)
}

DERIVATIVE states
{
	rate(v)
	mKv' = (infmKv - mKv)/taumKv
	hKv' =  (infhKv - hKv )/tauhKv

}


UNITSOFF

FUNCTION alphamKv(v(mV)) (/ms)
{ 
	alphamKv = (0.001)*5*(100-v)/( exp( (100-v)/42) -1 )
	:alter from orginal settings where it is in the unit of 1/s
}

FUNCTION  betamKv (v(mV)) (/ms)
{
	
	betamKv = (0.001)*9*exp (- (v-20) /40 )
}


FUNCTION alphahKv (v(mV)) (/ms)
{
	alphahKv = (0.001)*0.15 *exp (-v/22)
}

FUNCTION betahKv (v(mV)) (/ms)
{ 
	betahKv = (0.001)*0.4125/( exp ( ( 10-v)/7 ) +1 )

}

UNITSON

PROCEDURE rate(v (mV))
{
        LOCAL a, b

	
	a = alphamKv(v)
	b = betamKv(v)
	taumKv = 1/(a + b)
	infmKv = a/(a + b)
	
	a = alphahKv(v)
	b = betahKv(v)
	tauhKv = 1/(a + b)
	infhKv = a/(a + b)
	

}