Multicompartmental cerebellar granule cell model (Diwakar et al. 2009)

 Download zip file   Auto-launch 
Help downloading and running models
A detailed multicompartmental model was used to study neuronal electroresponsiveness of cerebellar granule cells in rats. Here we show that, in cerebellar granule cells, Na+ channels are enriched in the axon, especially in the hillock, but almost absent from soma and dendrites. Numerical simulations indicated that granule cells have a compact electrotonic structure allowing EPSPs to diffuse with little attenuation from dendrites to axon. The spike arose almost simultaneously along the whole axonal ascending branch and invaded the hillock, whose activation promoted spike back-propagation with marginal delay (<200 micros) and attenuation (<20 mV) into the somato-dendritic compartment. For details check the cited article.
1 . Diwakar S, Magistretti J, Goldfarb M, Naldi G, D'Angelo E (2009) Axonal Na+ channels ensure fast spike activation and back-propagation in cerebellar granule cells. J Neurophysiol 101:519-32 [PubMed]
Citations  Citation Browser
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: Cerebellum;
Cell Type(s): Cerebellum interneuron granule GLU cell;
Channel(s): I A; I M; I h; I K,Ca; I Sodium; I Calcium; I Potassium; I A, slow;
Gap Junctions:
Simulation Environment: NEURON;
Model Concept(s): Action Potential Initiation; Active Dendrites; Detailed Neuronal Models; Axonal Action Potentials; Action Potentials; Intrinsic plasticity;
Implementer(s): Diwakar, Shyam [shyam at];
Search NeuronDB for information about:  Cerebellum interneuron granule GLU cell; I A; I M; I h; I K,Ca; I Sodium; I Calcium; I Potassium; I A, slow;
AmpaCOD.mod *
GRC_CA.mod *
GRC_CALC.mod *
GRC_GABA.mod *
GRC_KA.mod *
GRC_KCA.mod *
GRC_KIR.mod *
GRC_KM.mod *
GRC_KV.mod *
GRC_LKG1.mod *
GRC_LKG2.mod *
GRC_NA.mod *
NmdaS.mod *
Pregen.mod *
// Detailed model of Cerebellar Granular Cell model
// Multicompartmental model - Initiation script
// Last updated 07-Jan-2009
// Model developer: Shyam Diwakar M.
// Developed at Egidio D'Angelo's Lab at Univ of Pavia
// Code contributors: Thierry Nieus, Sergio Solinas 
// Dept. of Gen. Physiology (Univ. of Pavia, Italy)
// School of biotech (Amrita University, India) 

/* Model published as [Diwakar et al, J.Neurophysiology] 
 Shyam Diwakar, Jacopo Magistretti, Mitchell Goldfarb, Giovanni Naldi, and Egidio D'Angelo.
 Axonal Na+ channels ensure fast spike activation and back-propagation in cerebellar granule cells, J Neurophysiol (December 10, 2008). 


// ***** General settings *****
tstop=200 //default simulation stop time in ms
v_init = -70 //init voltage
xopen("Grc_Cell.hoc") // load Granule cell template
objref Granule[1]  //create Granule cell
Granule[0] = new GrC()
// ***** Synapses ****

objref nclist,Mossy[4],Inhib[4],nclist2	
objref synNS[4],synA[4],synG[4]	

// ***** Procedures to connect synapses to dendritic tips *****
proc con1() {
	nclist2 = new List()
	for(j=0;j<4;j=j+1) {
	    //print j,k
	    access Granule[0].dend_3[j]	
	    Inhib[j] = new SpikeGenerator(0.5)
            synG[j] = new GRC_GABA(0.5)
            nclist2.append(new NetCon(Inhib[j], synG[j], -20, 0.000, 1e-3))
proc con2() { 
	nclist = new List()
       	for(k3=0;k3<4;k3=k3+1) {
		access Granule[0].dend_4[k3]
        	Mossy[k3] = new SpikeGenerator(0.5)
		synA[k3] = new AmpaCOD(0.5)
		synNS[k3] = new NMDAS(0.5)
	        nclist.append(new NetCon(Mossy[k3], synNS[k3],-20, 0.000, 1e-3))
	        nclist.append(new NetCon(Mossy[k3], synA[k3],-20, 0.000, 1e-3))


// ***** Start GUI *****


xopen("ComPanel.hoc") //Command Panel

// ***** Initialization *****


proc usetable(){
	usetable_GRC_NA  = 	$1
	usetable_GRC_NAR = 	$1
	usetable_GRC_PNA = 	$1
	usetable_GRC_KV  = 	$1
	usetable_GRC_KA  =  	$1
	usetable_GRC_KIR = 	$1
	usetable_GRC_KM  = 	$1
	usetable_GRC_CA  = 	$1

xopen("Parametri.hoc") //"Channels and Controls Panel"
access GrC[0].soma

xopen("") // A simple session file with a graph plotting membrane voltage across many compartments