//genesis
// by Kai DU, kai.du@ki.se
function create_CaR
str path = "CaR_channel"
float xmin = -0.10 /* minimum voltage we will see in the simulation */ // V
float xmax = 0.05 /* maximum voltage we will see in the simulation */ // V
int xdivsFiner = 3000
int c = 0
float gMax = 1.0 // random number, but to be modified later
/****** Begin vars used to enable genesis calculations ********/
float increment = (xmax - xmin)*1e3/xdivsFiner // mV
echo "naF: increment" {increment} "mV"
float x = -100.00 // mV
float minf = 0
float hinf = 0
float mvhalf = -8.46 // mV, ROBERT C. FOEHRING,et.al. 2000 fixed with 3 gates!
float mslope = 25.98 // mV, 25.98, 17.98
float hvhalf = -33.3 // mV, used in wolf's model,also from ROBERT C. FOEHRING,et.al. 2000
float hslope = 17 // wolf's model
// float hvhalf = -76 // mV,
// float hslope = 11 //
float mshift = 0.0 // mV
float hshift = 0.0 // mV
float taum = 0 // ms
float tauh = 0 // ms
float qfactor = 1 // experiment was done in room temperature
if({TEMPERATURE}>30)
qfactor = 3
end
/****** End vars used to enable genesis calculations **********/
pushe /library
create tabchannel {path}
call {path} TABCREATE X {xdivsFiner} {xmin} {xmax} // activation gate
call {path} TABCREATE Y {xdivsFiner} {xmin} {xmax} // inactivation gate
/* Defines the powers of m Hodgkin-Huxley equationref: ROBERT C. FOEHRING,et.al. 2000 */
setfield {path} Ek {Erev} Xpower 3 Ypower 1
/********************* taken from Wolf's model************************************/
// set tau_m table
create table CaR_taum // ms
call CaR_taum TABCREATE 1 {xmin} {xmax}
//the table corresponds to -100 mV to 50 mV
/********ROBERT C. FOEHRING,et.al. 2000 **************/
// taum ( 0mV ) = 1.7 was taken from FOEHRING,et.al. 2000
// taums are almost "constant" from -50mV to 10 mV according to Brevi 2001 (fig 11-D)
setfield CaR_taum table->table[0] 1.7 \
table->table[1] 1.7
create table CaR_tauh
call CaR_tauh TABCREATE 15 {xmin} {xmax}
//the table corresponds to -100 mV to 50 mV
setfield CaR_tauh table->table[0] 100 \
table->table[1] 100 \
table->table[2] 100 \
table->table[3] 100 \
table->table[4] 100 \
table->table[5] 100 \
table->table[6] 100 \
table->table[7] 100 \
table->table[8] 65 \
table->table[9] 35\
table->table[10] 30 \
table->table[11] 20 \
table->table[12] 20 \
table->table[13] 20 \
table->table[14] 20 \
table->table[15] 20
call CaR_taum TABFILL {xdivsFiner} 2
call CaR_tauh TABFILL {xdivsFiner} 2
for(c = 0; c < {xdivsFiner} + 1; c = c + 1)
minf = 1/(1 + {exp {-(x - mvhalf + mshift)/mslope}})
hinf = 1/(1 + {exp {(x - hvhalf + hshift)/hslope}})
taum = {getfield CaR_taum table->table[{c}]} //no need to use qfactor; it has been corrected
tauh = {getfield CaR_tauh table->table[{c}]}/qfactor
setfield {path} X_A->table[{c}] {taum*1e-3} // in the ROBERT C. FOEHRING,et.al. 2000, the tau was already fixed for m^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
/* fill the tables with the values of tau and minf/hinf
* calculated from tau and minf/hinf
*/
tweaktau {path} X
tweaktau {path} Y
create ghk {path}GHK
setfield {path}GHK Cout {Cout} // Carter & Sabatini 2004 uses 2mM,
// Wolf 5mM
setfield {path}GHK valency 2.0
setfield {path}GHK T {TEMPERATURE}
setfield {path} Gbar {gMax}
addmsg {path} {path}GHK PERMEABILITY Gk
end
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