TITLE KATP channel : Author: Chitaranjan Mahapatra (chitaranjan@iitb.ac.in) : Computational Neurophysiology Lab : Indian Institute of Technology Bombay, India : For details refer: : Mahapatra C, Brain KL, Manchanda R, A biophysically constrained computational model of the action potential : of mouse urinary bladder smooth muscle. PLOS One (2018) NEURON { SUFFIX KATP USEION atp READ atpi VALENCE -1 USEION k READ ek WRITE ik RANGE gbar, ik, tauo,oinf GLOBAL qdeltat,at,athf,ap, q10 } UNITS { (mA) = (milliamp) (mV) = (millivolt) (molar) = (1/liter) (mM) = (millimolar) } PARAMETER { qdeltat = 1 gbar = 0.001(mho/cm2) atpi = 0.0003 (mM) athf = 0.006 (mM) ek = -21 (mV) at = 10 ap =3 celsius = 37 (degC) dt (ms) q10=2.3 } ASSIGNED { v (mV) ik (mA/cm2) oinf tauo (ms) } STATE{ o } INITIAL{ rate(atpi) o = oinf } BREAKPOINT { SOLVE states METHOD cnexp ik = gbar * o * (v - ek) } DERIVATIVE states { rate(atpi) o' = (o-oinf ) / tauo } PROCEDURE rate(atpi(mM)) { LOCAL a,qt qt=q10^((celsius-37)/10) oinf = (1/ (1+ ((atpi/athf)^ap))) if (atpi < 0.005) { tauo = 1 - (186.67 * atpi)/qt } else { tauo = 2/qt } tauo = at * (tauo / qdeltat) } FUNCTION trap0(v,th,a,q) { if (fabs(v-th) > 1e-6) { trap0 = a * (v - th) / (1 - exp(-(v - th)/q)) } else { trap0 = a * q } }