// GENERATES AN IO CURVE OF RESPONSES TO STIMULATION OF INCREASING NUMBER OF EXCITATORY INPUTS IN SR AND SLM
// TESTS FOR CONTRIBUTION OF NMDARs AND EFFECT OF RECTIFYING TONIC INHIBITION
//
// This script:
// - runs a family of two simulations:
// stimulation in stratum rediatum and stratum lacunosum moleculare,
// same stimulation in the presence of AP5.
// For each simulation, membrane potentials are displayed for the soma, a proximal tuft
// dendrite, and a distal tuft dendrite. Additionally, shape plots are used
// to illustrate the location of excitatory and inhibitory synapses.
// Numerical parameters for simulation.
tstop = 220 // stop time of simulation
stimStart=20
dtime=0.2
stim_no=5
stim_inter=20
stim_delay=0
stim_noise=0
simul_iter=6
//seed of random number generator
randShift = 6.37
//specify levels of tonic inhibition
gtonic=1.e-4
objref TI_strength
TI_strength = new Vector()
TI_strength.append(0,0.5,1,5,10,50,100)
//parameters for rectifying and non rectifying part of GABAsynapses
GABAweight_total=0.0007
GABAweight0=GABAweight_total/5
GABAweight1=4*GABAweight_total/5
GABAtau2=30
GABAtau1=1.0
GABArelP=0.5
slope_factor=4
V50=-60
//establish rectifying and non-rectifying parts of GABA synapses
for ii=1,totVgatAt {
synGABA[ii-1].tau1= GABAtau1/2
synGABA[ii-1].tau2 = GABAtau2/2
synGABA[ii-1].slope_factor=0.3
synGABA[ii-1].V50=-150
synGABArect[ii-1].tau1= GABAtau1
synGABArect[ii-1].tau2 = GABAtau2
synGABArect[ii-1].slope_factor=slope_factor
synGABArect[ii-1].V50=V50
}
//connect synapses
load_file("Generate_Stimulator.hoc")
load_file("Connect_Stimulator2ExcSyn.hoc")
load_file("Connect_Stimulator2InhSyn.hoc")
//setup recording vectors etc.
objref recv_tuft1, recv_tuft2, recv_tuft3, recv_soma, rect
objref recv_obl1, recv_obl2, recv_obl3, filenames[6]
strdef ColLabel, file_name, file_name1, file_name2, file_name3, file_name4, file_name5, file_name6, file_name7
objref outfile, storeM, storeM_control, storeM_TI_X1, storeM_TI_X10, storeM_TI_X100, storeM_TI_X1000, storeM_TI_X10000
load_file("Print-to-File.hoc")
ColLabel = "Membrane potential"
file_name1="C:/../TI_X0.atf"
file_name2="C:/../TI_X05.atf"
file_name3="C:/../TI_X1.atf"
file_name4="C:/../TI_X5.atf"
file_name5="C:/../TI_X10.atf"
file_name6="C:/../TI_X50.atf"
file_name7="C:/../TI_X100.atf"
recv_soma = new Vector()
recv_tuft1 = new Vector()
recv_tuft2 = new Vector()
recv_tuft3 = new Vector()
recv_obl1 = new Vector()
recv_obl2 = new Vector()
recv_obl3 = new Vector()
rect = new Vector()
recv_soma.record(&soma.sec.v(0.5),dtime)
rect.record(&t)
rec_conditions=14
storeM_control = new Matrix(tstop/dtime+1,rec_conditions*simul_iter)
storeM_TI_X1 = new Matrix(tstop/dtime+1,rec_conditions*simul_iter)
storeM_TI_X10 = new Matrix(tstop/dtime+1,rec_conditions*simul_iter)
storeM_TI_X100 = new Matrix(tstop/dtime+1,rec_conditions*simul_iter)
storeM_TI_X1000 = new Matrix(tstop/dtime+1,rec_conditions*simul_iter)
storeM_TI_X10000 = new Matrix(tstop/dtime+1,rec_conditions*simul_iter)
nExcAct_SLM = 50// number of excitatory synapses to activate, ~3.3% of 1464 total with spine density of 0.5/um2
nInhAct_SLM = 95 // number of inhibitory synapses to activate; 34% of 280 total
nExcAct_SR = 200//number of excitatory synapses to activate, ~3% of 6000 total (oblique plus trunk)
nInhAct_SR = 50 //number of inhibitory synapses to activate; 34% of 145 total
load_file("update_Synapses.hoc")
// Parameters for visualisation. dendInd1 and dendInd2 refer to dendritic
// indices that will have voltage traces plotted.
dendInd1 = 107 // left apical, SLM
dendInd2 = 149 // left apical, terminal neurite, SLM
dendInd3 = 176 // SLM
dendInd4 = 186 // SR
dendInd5 = 144 // SR
dendInd6 = 136 // SR
objref dend1Ref,dend2Ref,dend3Ref,dend4Ref,dend5Ref,dend6Ref
Cell[0].dend[dendInd1] {dend1Ref = new SectionRef()}
Cell[0].dend[dendInd2] {dend2Ref = new SectionRef()}
Cell[0].dend[dendInd3] {dend3Ref = new SectionRef()}
Cell[0].dend[dendInd4] {dend4Ref = new SectionRef()}
Cell[0].dend[dendInd5] {dend5Ref = new SectionRef()}
Cell[0].dend[dendInd6] {dend6Ref = new SectionRef()}
recv_tuft1.record(&dend1Ref.sec.v(0.5),dtime)
recv_tuft2.record(&dend2Ref.sec.v(0.5),dtime)
recv_tuft3.record(&dend3Ref.sec.v(0.5),dtime)
recv_obl1.record(&dend4Ref.sec.v(0.5),dtime)
recv_obl2.record(&dend5Ref.sec.v(0.5),dtime)
recv_obl3.record(&dend6Ref.sec.v(0.5),dtime)
// Determine number of segments to track.
totSegs = 0
forall { for (x,0) { totSegs +=1 } }
// Create shape plots
strdef shape_label
objref shapeExc[simul_iter],shapeInh
for (ii=1;ii<simul_iter+1; ii=ii+1){
sprint(shape_label,"Exc, %d",ii)
print shape_label
shapeExc[ii-1] = new Shape()
shapeExc[ii-1].label(shape_label)
}
shapeInh = new Shape()
shapeInh.label("Inh")
// Create vectors that will store indices of active excitatory and
// inhibitory synapses.
objref curExc_SLM, curExc_SR, curInh_SLM, curInh_SR
// Vectors of release of normalised release probability
objref norm_Pr_exc, norm_Pr_inh_SR, norm_Pr_inh_SLM, ActSyn, ActSyn_inh, SynAct
// Initialise simulations by adding channels and assigning genotypes to
// inhibitory synapses.
initChannels()
seedGenotypes()
// Implement short-term plasticity at excitatory synapses
norm_Pr_exc = new Vector(5) //
ActSyn = new Vector(5)
norm_Pr_exc.x[0] = 1
norm_Pr_exc.x[1] = 1.5
norm_Pr_exc.x[2] = 1.8
norm_Pr_exc.x[3] = 1.9
norm_Pr_exc.x[4] = 2.0
// DO SIMULATION AND PLOT RESULTS.
// turn off cvode variable time step in order to avoid errors during repetitive simulations
cvode_active(0)
// activate inhibitory inputs
activateInhibition(cellList,-1,1) // clear inhibition
curInh_SR = activateInhibition(radiatumList,nInhAct_SR,randShift,"vgat",1)
curInh_SLM = activateInhibition(tuftList,nInhAct_SLM,randShift,"vgat",1)
// Implement short-term plasticity at inhibitory synapses in stratum radiatum
norm_Pr_inh_SR = new Vector(5) //
ActSyn_inh = new Vector(5)
norm_Pr_inh_SR.x[0] = 1
norm_Pr_inh_SR.x[1] = 0.7
norm_Pr_inh_SR.x[2] = 0.7
norm_Pr_inh_SR.x[3] = 0.7
norm_Pr_inh_SR.x[4] = 0.7
// Define activated inhibitory synapses
ActSyn_inh = set_InhSyn_fixed_N(curInh_SR, randShift/3, GABArelP, norm_Pr_inh_SR, shapeInh)
print "In SR, the number of activated inhibitory synapses at each pulse are: ",ActSyn_inh.x[0], ", " , ActSyn_inh.x[1], ", " , ActSyn_inh.x[2], ", " , ActSyn_inh.x[3], ", " , ActSyn_inh.x[4]
// Implement short-term plasticity at inhibitory synapses in stratum lacunosum moleculare
norm_Pr_inh_SLM = new Vector(5) //
ActSyn_inh = new Vector(5)
norm_Pr_inh_SLM.x[0] = 1
norm_Pr_inh_SLM.x[1] = 0.6
norm_Pr_inh_SLM.x[2] = 0.5
norm_Pr_inh_SLM.x[3] = 0.4
norm_Pr_inh_SLM.x[4] = 0.4
ActSyn_inh = set_InhSyn_fixed_N(curInh_SLM, randShift/4, GABArelP, norm_Pr_inh_SLM, shapeInh)
print "In SLM, the number of activated inhibitory synapses at each pulse are: ",ActSyn_inh.x[0], ", " , ActSyn_inh.x[1], ", " , ActSyn_inh.x[2], ", " , ActSyn_inh.x[3], ", " , ActSyn_inh.x[4]
// run simulation with increasing tonic inhibition
load_file("SynStim_SR_SLM_TI.hoc")