//genesis - tutorial2.g - GENESIS Version 2.0 /*====================================================================== A sample script to create a soma-like compartment. SI units are used. ======================================================================*/ float PI = 3.14159 // soma parameters - chosen to be the same as in SQUID (but in SI units) float RM = 0.33333 // specific membrane resistance (ohms m^2) float CM = 0.01 // specific membrane capacitance (farads/m^2) float RA = 0.3 // specific axial resistance (ohms m) float EREST_ACT = -0.07 // resting membrane potential (volts) float Eleak = EREST_ACT + 0.0106 // membrane leakage potential (volts) float ENA = 0.045 // sodium equilibrium potential float EK = -0.082 // potassium equilibrium potential // cell dimensions (meters) float soma_l = 30e-6 // cylinder equivalent to 30 micron sphere float soma_d = 30e-6 float dt = 0.00005 // simulation time step in sec setclock 0 {dt} // set the simulation clock //=============================== // Function Definitions //=============================== function makecompartment(path, length, dia, Erest) str path float length, dia, Erest float area = length*PI*dia float xarea = PI*dia*dia/4 create compartment {path} setfield {path} \ Em { Erest } \ // volts Rm { RM/area } \ // Ohms Cm { CM*area } \ // Farads Ra { RA*length/xarea } // Ohms end function make_Vmgraph float vmin = -0.100 float vmax = 0.05 float tmax = 0.100 // default simulation time = 100 msec create xform /data create xgraph /data/voltage setfield ^ xmax {tmax} ymin {vmin} ymax {vmax} create xbutton /data/RESET -script reset create xbutton /data/RUN -script "step "{tmax}" -time" create xbutton /data/QUIT -script quit xshow /data end //=============================== // Main Script //=============================== create neutral /cell // create the soma compartment "/cell/soma" makecompartment /cell/soma {soma_l} {soma_d} {Eleak} // provide current injection to the soma setfield /cell/soma inject 0.3e-9 // 0.3 nA injection current // make the graph to display soma Vm and pass messages to the graph make_Vmgraph addmsg /cell/soma /data/voltage PLOT Vm *volts *red check reset