Principles governing the operation of synaptic inhibition in dendrites (Gidon & Segev 2012)

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Accession:226401
A simple result of Gidon & Segev 2012 was provided where distal (off-path) inhibition is demonstrated to be more effective than proximal (on-path) inhibition in a ball and stick neuron.
Reference:
1 . Gidon A, Segev I (2012) Principles governing the operation of synaptic inhibition in dendrites. Neuron 75:330-41 [PubMed]
Model Information (Click on a link to find other models with that property)
Model Type: Neuron or other electrically excitable cell;
Brain Region(s)/Organism:
Cell Type(s):
Channel(s):
Gap Junctions:
Receptor(s):
Gene(s):
Transmitter(s):
Simulation Environment: NEURON;
Model Concept(s): Simplified Models; Synaptic Integration;
Implementer(s): Morse, Tom [Tom.Morse at Yale.edu];
//driver.hoc
// runs multiple simulations and stores the results

objref pc
pc = new ParallelContext()
strdef s

min_num_syn = 1
max_num_syn = 30
min_pois_rate = 1
max_pois_rate = 25

min_num_syn = 3
max_num_syn = 30
min_pois_rate = 3
max_pois_rate = 15

// test values 200 - fast, 1000 takes about a minute,  2000 took 3 minutes (39 CPU)
// 3000 took 5 minutes (59:35 CPU)
// 50000 took 80 some minutes
// 200000 is predicted to take 6 hours
tstop = 200000 // 20 seconds of run time brings statistical significance
// small for test runs them 50000 for production

objref output_file 
output_file = new File()

system("date")

strdef folder, filename
objref inhib_gmaxs
inhib_gmaxs=new Vector()
inhib_gmaxs.append(1,2,3,4,5,6,7,8,9,10,11,12) // had 1,10 earlier
// chose 12 gmaxs so could distribute over 12 cores where the 
// pc.id from 0 to 11 will be the index into inhib_gmaxs

proc run_over_synapses() {
  for num_of_synapses = min_num_syn,max_num_syn { // could be 1 30
    num_of_Ereceptors = num_of_synapses
    loclocation()
    init()
    my_run()
    output_file.printf("%d %-20.10g\n",num_of_synapses, ave_f)
  }
  // reset the number of receptors back to the default
  num_of_Ereceptors = 20
  loclocation()
}

proc run_over_rate() {
  for(rate=min_pois_rate; rate <= max_pois_rate; rate=rate+1) {  // could be 1 to 25
    ETspike = 1000/rate // period in milliseconds
    loclocation()
    init()
    my_run()
    output_file.printf("%d %-20.10g\n",rate, ave_f)
  }
  // reset rate back to default
  ETspike = 1000/20 // default 50 ms period for 20 Hz
  loclocation()
}

{
  inhib_index = pc.id
  system("hostname", s)
  printf("There are %d processes. My rank is %d so inhib_index = %d and I am on %s\n", pc.nhost, pc.id, inhib_index, s)
// instead of the below loop will farm out to different cores
// for inhib_index=0, inhib_gmaxs.size()-1 {
  sprint(folder,"%dnS",inhib_gmaxs.x[inhib_index])
  print folder

if (0) { // remove this section 20140219
  // change the ranges so that when there is more inhibition there is more excitation
//take range modification out?
  min_pois_rate = min_pois_rate + inhib_index
  max_pois_rate = max_pois_rate + inhib_index
  min_num_syn = min_num_syn + inhib_index
  max_num_syn = max_num_syn + inhib_index
  // shift the range a bit more number of e synapses case and increasing inhibition
   if (inhib_gmaxs.x[inhib_index] > 6) {
    min_num_syn = min_num_syn + 5
    max_num_syn = max_num_syn + 5
  }
} // removed modification of changing range of num of esyns
  ggabamax_prox = inhib_gmaxs.x[inhib_index]
  ggabamax_dist = inhib_gmaxs.x[inhib_index]
  
  // first explore firing rate in uninhibited dendrite as function of
  // number of excitatory synapses in hot spot
  
  // in test runs 4 gave rate = 0.95 Hz, 14 gave rate = 39.5 Hz,
  // the paper claimed 20, however 20 gave rate = 58.7 Hz
  
  output_file = new File()
  sprint(filename, "%s/SynNum_Rate.dat", folder)
  output_file.wopen(filename)
  print "running cntrl case (no inhib) over num of synapses"
  prox_inhib = 0
  dist_inhib = 0
  loclocation()
  
  run_over_synapses()
  
  output_file.close()
  if (0) { // ommit section 20140218
  sprint(filename, "%s/SynRate_CellRate.dat", folder)
  output_file.wopen(filename)
  
  print "running cntrl case over poisson rates of excit syn. activation"
  run_over_rate()
  
  output_file.close()
  }

  /////////////////////////////////////////////////////
  // proximal inhibition studies
  // 
  
  // first study with shunting reversal potential
  // this means the inhibitory rev pot is the resting pot
  
  inhibitory_erev = -65
  reset_inhib_erev()
  
  prox_inhib=1
  dist_inhib=0
  loclocation()
  
  print "ZoidSyn[0].number=",ZoidSyn[0].number
  print "ZoidSyn[1].number=",ZoidSyn[1].number
  sprint(filename, "%s/ProxInhib_Syn_CellRate.dat", folder)
  output_file.wopen(filename)
  
  print "running prox inhib over num of syn"
  run_over_synapses()
  
  output_file.close()
  
  if (0) { // ommit section 20140218
  sprint(filename, "%s/ProxInhib_SynRate_CellRate.dat", folder)
  output_file.wopen(filename)
  
  print "running prox inhib over poisson rates"
  run_over_rate()
  
  output_file.close()
  }  
  // change inhibition to distal
  
  print "running dist inhib over num of syn"
  
  // now turn off the prox inhibition
  // and on the dist inhib
  prox_inhib = 0
  dist_inhib = 1
  loclocation()
  print "inhibitory[1].number=",inhibitory[1].number
  print "ZoidSyn[0].number=",ZoidSyn[0].number
  print "ZoidSyn[1].number=",ZoidSyn[1].number
  
  sprint(filename, "%s/DistInhib_Syn_CellRate.dat", folder)
  output_file.wopen(filename)
  
  run_over_synapses()
  
  output_file.close()
  
  if (0) { // ommit section 20140218
  print "running dist inhib over cell rate"
  sprint(filename, "%s/DistInhib_SynRate_CellRate.dat", folder)
  output_file.wopen(filename)
  
  run_over_rate()
  
  output_file.close()
  }
// } // loop over different inhib max conductances
// verify eNa's
dendrite { print "dendrite eNa_traub = ", eNa_traub }
soma { print "soma eNa_traub = ",eNa_traub }

system("date")
} // end of run over a runworker or the master which
// took the place of the loop over inhib max conductances
{pc.runworker()}
{pc.done()}
quit()

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