Febrile seizure-induced modifications to Ih (Chen et al 2001)

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Accession:8284
Modeling and experiments in the paper Chen K,Aradi I, Thom N,Eghbal-Ahmadi M, Baram TZ, and Soltesz I (2001) support the hypothesis that modified Ih currents strongly influence inhibitory inputs in CA1 cells and that the depolarizing shift in Ih activation plays a primary role in this process. Please see the paper for details. Some modeling details are available at http://www.ucihs.uci.edu/anatomy/soltesz/supp.htm Correspondance should be addressed to isoltesz@uci.edu (modeling was done by Ildiko Aradi, iaradi@uci.edu)
Reference:
1 . Chen K, Aradi I, Thon N, Eghbal-Ahmadi M, Baram TZ, Soltesz I (2001) Persistently modified h-channels after complex febrile seizures convert the seizure-induced enhancement of inhibition to hyperexcitability. Nat Med 7:331-7 [PubMed]
Citations  Citation Browser
Model Information (Click on a link to find other models with that property)
Model Type: Channel/Receptor;
Brain Region(s)/Organism:
Cell Type(s): Hippocampus CA1 pyramidal GLU cell;
Channel(s): I Na,t; I K; I h;
Gap Junctions:
Receptor(s):
Gene(s):
Transmitter(s):
Simulation Environment: NEURON;
Model Concept(s): Action Potential Initiation; Activity Patterns; Bursting; Ion Channel Kinetics; Action Potentials; Epilepsy; Rebound firing;
Implementer(s): Aradi, Ildiko [IAradi at uci.edu];
Search NeuronDB for information about:  Hippocampus CA1 pyramidal GLU cell; I Na,t; I K; I h;
/* 
Chen et al. Nat. Medicine 2001 (modeling by Ildiko Aradi, iaradi@uci.edu)
Ih channel kinetics characteristic to Control animal; cell depolarized just below
firing threshold; increasing densities of Ih along the somatodendritic axis, 
train of IPSPs coming to the perisomatic region does NOT lead to rebound firing */

secondorder=2 
tstep=0
period=10
dt=0.01
tstop=2000
steps_per_ms=10

	begintemplate Cell
create soma, adend1, adend2, adend3, bdend, axon
public soma, adend1, adend2, adend3, bdend, axon

objectvar stim1, stim2

nsy=18

	objectvar syd[nsy]
double syddeadtime[nsy], sydgsbar[nsy]
double sydtau1[nsy], sydtau2[nsy], sydes[nsy]

proc init() {

	soma {nseg=1 L=20 diam=20}
	
	adend1 {nseg=1 L=150 diam=2}
	adend2 {nseg=1 L=150 diam=2}
	adend3 {nseg=1 L=150 diam=2}
	
	bdend {nseg=2 L=200 diam=2}
	axon {nseg=2 L=100 diam=0.5}

	connect axon(0), soma(1)

	connect adend1(0), soma(0.5)
	connect adend2(0), adend1(1)
	connect adend3(0), adend2(1)

	connect bdend(1), soma(0)

	    	soma {insert ichan
	gnatbar_ichan=0.12
	gkfbar_ichan=0.01
	insert hyperso
	ghyfbar_hyperso=0.0000
	ghysbar_hyperso=0.0000
	ghyhtfbar_hyperso=0.0015
	ghyhtsbar_hyperso=0.0015} 


	  	adend1 {insert ichan
	gnatbar_ichan=0.05
	gkfbar_ichan=0.01
	insert hyperde1
	ghyfbar_hyperde1=0.0048
	ghysbar_hyperde1=0.0048
	ghyhtfbar_hyperde1=0.00
	ghyhtsbar_hyperde1=0.00} 

	  	adend2 {insert ichan
	gnatbar_ichan=0.05
	gkfbar_ichan=0.01
	insert hyperde2
	ghyfbar_hyperde2=0.008
	ghysbar_hyperde2=0.008
	ghyhtfbar_hyperde2=0.00
	ghyhtsbar_hyperde2=0.00} 

	  	adend3 {insert ichan
	gnatbar_ichan=0.05
	gkfbar_ichan=0.01
	insert hyperde3
	ghyfbar_hyperde3=0.011
	ghysbar_hyperde3=0.011
	ghyhtfbar_hyperde3=0.0
	ghyhtsbar_hyperde3=0.0} 

	  	bdend {insert ichan
	gnatbar_ichan=0.05
	gkfbar_ichan=0.01
	insert hyperde1
	ghyfbar_hyperde1=0.00
	ghysbar_hyperde1=0.00
	ghyhtfbar_hyperde1=0.000
	ghyhtsbar_hyperde1=0.000} 
  	

		axon {insert ichan
	gnatbar_ichan=0.21
	gkfbar_ichan=0.01
	insert hyperso
	ghyfbar_hyperso=0.00
	ghysbar_hyperso=0.00
	ghyhtfbar_hyperso=0.000
	ghyhtsbar_hyperso=0.000} 

	forall {Ra=210}	
	forall {enat=50 ekf=-70 ehyf=-40 ehys=-40 
					ehyhtf=-40 ehyhts=-40
		gl_ichan=0.00025 el_ichan=-63 cm=1}


soma stim1 = new IClamp(0.5)
stim1.del=0
stim1.dur=2700
stim1.amp=0.1313

soma stim2 = new IClamp(0.5)
stim2.del=50
stim2.dur=1000
stim2.amp=0.0


/* pp synapses perisomatically*/

Tp = 20
del=250

	for k=0,5{
sydgsbar[k]=0.01
sydtau1[k]=1
sydtau2[k]=10
sydes[k]=-65
syddeadtime[k]=del+k*Tp 

soma syd[k] = new ppsyn(0.5)

{syd[k].gsbar=sydgsbar[k] 
syd[k].tau1=sydtau1[k] 
syd[k].tau2=sydtau2[k] 
syd[k].es=sydes[k]
syd[k].deadtime=syddeadtime[k]}
			}

	for s=6,11{
sydgsbar[s]=0.01
sydtau1[s]=1
sydtau2[s]=10
sydes[s]=-65
syddeadtime[s]=del+(s-6)*Tp 

adend1 syd[s] = new ppsyn(0.5)

{syd[s].gsbar=sydgsbar[s] 
syd[s].tau1=sydtau1[s] 
syd[s].tau2=sydtau2[s] 
syd[s].es=sydes[s]
syd[s].deadtime=syddeadtime[s]}
			}
	for s=12,17{
sydgsbar[s]=0.01
sydtau1[s]=1
sydtau2[s]=10
sydes[s]=-65
syddeadtime[s]=del+(s-12)*Tp 

axon syd[s] = new ppsyn(0.1)

{syd[s].gsbar=sydgsbar[s] 
syd[s].tau1=sydtau1[s] 
syd[s].tau2=sydtau2[s] 
syd[s].es=sydes[s]
syd[s].deadtime=syddeadtime[s]}
			}


		}

	endtemplate Cell

objectvar cell

cell = new Cell()

/* original graph commented out

objref g1

g1 = new Graph()
g1.size(0,tstop,-100,50)
g1.addexpr("cell.soma.v(0.5)",2,1)
/* g1.addexpr("cell.adend1.v(0.5)",3,1)
g1.addexpr("cell.adend2.v(0.5)",4,1)
g1.addexpr("cell.adend3.v(0.5)",5,1) */

/* g1.addexpr("cell.adend1.v(0.5)",1,1)
g1.addexpr("cell.adend2.v(0.5)",3,1)
g1.addexpr("cell.adend3.v(0.5)",4,1) */

/*
proc label() {
	g1.color(1)
	g1.vfixed(1)
	g1.label(0, .5, "mV")
	g1.label(.4, .15, "t (ms)")
	g1.label(.1, .01, "divers")
}
*/

// label()

// simulation control


finitialize(-50)

/*
proc pl() {
g1.begin()
while(t<tstop) {
if (tstep%period==0){
g1.plot(t)
g1.fastflush()
print t, cell.soma.v(0.5)
doNotify()}
tstep=tstep+1
fadvance()
}
g1.flush()
doNotify()
}
*/

// pl() // graphing is now done in mosinit.hoc