Synchronicity of fast-spiking interneurons balances medium-spiny neurons (Damodaran et al. 2014)

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This study investigates the role of feedforward and feedback inhibition in maintaining the balance between D1 and D2 MSNs of the striatum. The synchronized firing of FSIs are found to be critical in this mechanism and specifically the gap junction connections between FSIs.
1 . Damodaran S, Evans RC, Blackwell KT (2014) Synchronized firing of fast-spiking interneurons is critical to maintain balanced firing between direct and indirect pathway neurons of the striatum. J Neurophysiol 111:836-48 [PubMed]
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Model Information (Click on a link to find other models with that property)
Model Type: Realistic Network;
Brain Region(s)/Organism:
Cell Type(s): Neostriatum medium spiny direct pathway GABA cell; Neostriatum medium spiny indirect pathway GABA cell; Neostriatum fast spiking interneuron;
Gap Junctions: Gap junctions;
Receptor(s): NMDA; Gaba;
Simulation Environment: GENESIS;
Model Concept(s): Detailed Neuronal Models; Parkinson's;
Implementer(s): Blackwell, Avrama [avrama at]; Damodaran, Sriraman [dsriraman at];
Search NeuronDB for information about:  Neostriatum medium spiny direct pathway GABA cell; Neostriatum medium spiny indirect pathway GABA cell; NMDA; Gaba;
ampa_channel.g *
BKKchannel.g *
CaL12inact_channel.g *
CaL13_channel.g *
CaNinact_channel.g *
CaR_channel.g *
CaT_channel.g *
gaba_channel.g *
K_DR_channel.g *
kAf_chanRE.g *
kAs_chanRE.g *
kIR_chanKD.g *
naF_chanOg.g *
nmda_channel.g *
SKchannelCaDep.g *
synaptic_channel.g *
tabchanforms.g *

function make_NMDA_channel (chanpath, Ek, KMg, tau2, gmax, ghk)

  str chanpath //what you want the channel to be called (full path)
  float KMg, tau2, gmax  //parameters that differ between NR2A, B, C and D subunits
  float Ek
  int ghk 
  float tau1 = (4.4624e-3)/2 //  DE Chapman et al 2003, table 1 (12.13/e=5.63ms)
  float CMg = 1  // [Mg] in mM

  float eta = 1/3.57  // per mM
  float gamma = 62  // per Volt

	echo "chanpath = "{chanpath}
	echo "caBuffer = "{Ek}
	echo "KMg = "{KMg}
	echo "tau2 = "{tau2}
	echo "gmax = "{gmax}

	create synchan {chanpath}
	setfield {chanpath} \
          Ek   {Ek}   \
          tau1 {tau1} \
          tau2 {tau2} \
          gmax {gmax/2}
//the kinetics of the magnesium block is different for different subunits.  
// NR2A and B are about the same, but C and D are much less affected by the block.  
//these numbers were used because the made the magnesium block curve fit the figures by Moyner et al (1994 figure 7) best by eye.

  create Mg_block {chanpath}/block
  setfield {chanpath}/block CMg {CMg} 
  setfield {chanpath}/block KMg_B {1.0/{gamma}}
  setfield {chanpath}/block KMg_A {KMg}
  addmsg {chanpath} {chanpath}/block CHANNEL Gk Ek

  if (ghk==1)
     create ghk {chanPath}/GHK
     setfield {chanPath}/GHK Cout 2 // Carter & Sabatini 2004 uses 2mM, Wolf 5mM
     setfield {chanPath}/GHK valency 2.0
     setfield {chanPath}/GHK T {temperature}
     addmsg {compPath}/{chanpath}/block {chanPath}/GHK PERMEABILITY Gk