: Rod PhotoReceptor h channel NEURON { SUFFIX h NONSPECIFIC_CURRENT ih RANGE gh, ghbar, Vhalfh, Sh RANGE eh, aoh } UNITS { (mA) = (milliamp) (mV) = (millivolt) (mS) = (millimho) } PARAMETER { ghbar = 1.41 (mS/cm2) <0,1e9> eh = -32 (mV) Vhalfh=-82 (mV) Sh = -5.33 (mV) aoh = 1.64 (/s) } STATE { nh } ASSIGNED { v (mV) ih (mA/cm2) infh tauh (ms) gh (mho/cm2) } INITIAL { rate(v) nh = infh } BREAKPOINT { SOLVE states METHOD cnexp gh = (0.001)*ghbar*nh ih = gh*(v - eh) } DERIVATIVE states { rate(v) nh' = (infh - nh )/tauh } FUNCTION alphah(v(mV)) (/ms) { alphah = 0.001*aoh*exp( (v - Vhalfh)/(2*Sh) ) } FUNCTION betah(v(mV)) (/ms) { betah =0.001*aoh*exp( - ( v-Vhalfh)/(2*Sh) ) } PROCEDURE rate(v (mV)) { LOCAL ah, bh ah = alphah(v) bh = betah(v) tauh = 1/(ah + bh) infh = ah*tauh }