//genesis function make_KIR_channel float Erev = -0.09 // V str path = "KIR_channel" float xmin = -0.15 /* minimum voltage we will see in the simulation */ // V float xmax = 0.05 /* maximum voltage we will see in the simulation */ // V int xdivsFiner = 4000 int c = 0 /****** Begin vars used to enable genesis calculations ********/ float increment = (xmax - xmin)*1e3/xdivsFiner // mV echo "KIR increment:" {increment} "mV" float x = -150.00 float minf = 0 float hinf = 0 float mvhalf = -52.0 // mV float mshift = 50.0 // 30, mV Shen, et,al. 2007 Nat. Neurosci. supplementary table 1 float mslope = 13.0 // mV float taum = 0 // ms float tauh = 0 // ms /****** End vars used to enable genesis calculations **********/ create tabchannel {path} call {path} TABCREATE X {xdivsFiner} {xmin} {xmax} // activation gate // call {path} TABCREATE Y {xdivsFiner} {xmin} {xmax} // inactivation gate, no longer used float qfactor = 3 // to match in vitro data, Wolf,et.al.2005 create table kir_taum // ms call kir_taum TABCREATE 20 {xmin} {xmax} //the table corresponds to -150 mV to 50 mV, digitally extracted from JE Steephen,et.al. 2009, fig1 setfield kir_taum table->table[0] 0.2 \ table->table[1] 0.2 \ table->table[2] 0.2 \ table->table[3] 0.2 \ table->table[4] 0.2 \ table->table[5] 0.38 \ table->table[6] 0.97 \ table->table[7] 1.486 \ table->table[8] 5.3763 \ table->table[9] 6.0606 \ table->table[10] 6.8966 \ table->table[11] 7.6923 \ table->table[12] 7.1429 \ table->table[13] 5.8824 \ table->table[14] 4.4444 \ table->table[15] 4.0 \ table->table[16] 4.0 \ table->table[17] 4.0 \ table->table[18] 4.0 \ table->table[19] 4.0 \ table->table[20] 4.0 call kir_taum TABFILL {xdivsFiner} 2 // table for hinf // In Steephen's paper, there are only three hinf values, corresponding to -120,-90 and -50 mV. // to expand table from -150 mV to +50 mV, I set hinf(<-120mV) = hinf(-120mV), hinf(-50 mV) = hinf(>-50mV) /* We might not need inactivation gate now create table kir_hinf call kir_hinf TABCREATE 20 {xmin} {xmax} setfield kir_hinf table->table[0] 0.53 \ table->table[1] 0.53 \ table->table[2] 0.53 \ table->table[3] 0.53 \ table->table[4] 0.55 \ table->table[5] 0.57 \ table->table[6] 0.59 \ table->table[7] 0.6925 \ table->table[8] 0.7950 \ table->table[9] 0.8975 \ table->table[10] 1.0 \ table->table[11] 1.0 \ table->table[12] 1.0 \ table->table[13] 1.0 \ table->table[14] 1.0 \ table->table[15] 1.0 \ table->table[16] 1.0 \ table->table[17] 1.0 \ table->table[18] 1.0 \ table->table[19] 1.0 \ table->table[20] 1.0 call kir_hinf TABFILL {xdivsFiner} 2 //table for tauh create table kir_tauh call kir_tauh TABCREATE 20 {xmin} {xmax} setfield kir_tauh table->table[0] 7.8 \ table->table[1] 7.8 \ table->table[2] 7.8 \ table->table[3] 7.8 \ table->table[4] 10.2 \ table->table[5] 12.6 \ table->table[6] 15.0 \ table->table[7] 17.575 \ table->table[8] 20.15 \ table->table[9] 22.725 \ table->table[10] 25.3 \ table->table[11] 25.3 \ table->table[12] 25.3 \ table->table[13] 25.3 \ table->table[14] 25.3 \ table->table[15] 25.3 \ table->table[16] 25.3 \ table->table[17] 25.3 \ table->table[18] 25.3 \ table->table[19] 25.3 \ table->table[20] 25.3 call kir_tauh TABFILL {xdivsFiner} 2 */ /*fills the tabchannel with values for KIR_alpha & KIR_beta*/ for(c = 0; c < {xdivsFiner} + 1; c = c + 1) minf = 1/(1 + {exp {(x - mvhalf + mshift)/mslope}}) // hinf = {getfield kir_hinf table->table[{c}]} taum = {getfield kir_taum table->table[{c}]}/qfactor // tauh = {getfield kir_tauh table->table[{c}]} setfield {path} X_A->table[{c}] {taum*1e-3} setfield {path} X_B->table[{c}] {minf} // setfield {path} Y_A->table[{c}] {tauh*1e-3} // setfield {path} Y_B->table[{c}] {hinf} x = x + increment end /* Defines the powers of m Hodgkin-Huxley equation*/ setfield {path} Ek {Erev} Xpower 1 Ypower 0 /* fill the tables with the values of tau and minf/hinf * calculated from tau and minf/hinf */ tweaktau {path} X // tweaktau {path} Y end