Electrotonic transform and EPSCs for WT and Q175+/- spiny projection neurons (Goodliffe et al 2018)

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Accession:236310
This model achieves electrotonic transform and computes mean inward and outward attenuation from 0 to 500 Hz input; and randomly activates synapses along dendrites to simulate AMPAR mediated EPSCs. For electrotonic analysis, in Elec folder, the entry file is MSNelec_transform.hoc. For EPSC simulation, in Syn folder, the entry file is randomepsc.hoc. Run read_EPSCsims_mdb_alone.m next with the simulated parameter values specified to compute the mean EPSC.
Reference:
1 . Goodliffe JW, Song H, Rubakovic A, Chang W, Medalla M, Weaver CM, Luebke JI (2018) Differential changes to D1 and D2 medium spiny neurons in the 12-month-old Q175+/- mouse model of Huntington's Disease. PLoS One 13:e0200626 [PubMed]
Citations  Citation Browser
Model Information (Click on a link to find other models with that property)
Model Type: Synapse;
Brain Region(s)/Organism: Striatum;
Cell Type(s): Neostriatum spiny neuron;
Channel(s):
Gap Junctions:
Receptor(s): AMPA;
Gene(s):
Transmitter(s):
Simulation Environment: NEURON;
Model Concept(s): Detailed Neuronal Models; Membrane Properties; Electrotonus; Synaptic-input statistic;
Implementer(s):
Search NeuronDB for information about:  AMPA;
/
GoodliffeEtAl2018
Elec
tau_tables
kir.mod *
actionPotentialPlayer.hoc *
all_tau_vecs.hoc
analyticFunctions.hoc *
aux_procs.hoc
baseline_values.txt
basic_procs.hoc
colorDendrites.hoc
electro_procs.hoc *
fixnseg.hoc *
load_scripts.hoc *
measureMeanAtten.hoc
MSN_fixDiams.hoc
MSNelect.hoc
MSNelect_transform.hoc
Nov3IR3a.hoc
Nov9IR2a_spine.hoc
readcell.hoc
                            
TITLE Kir potassium current for nucleus accumbens (IRK1 = Kir 2.1 - see Mermelstein)

COMMENT 

Mermelstein PG, Song WJ, Tkatch T, Yan Z, Surmeier DJ (1998) Inwardly
rectifying potassium (IRK) currents are correlated with IRK subunit
expression in rat nucleus accumbens medium spiny neurons. J Neurosci
18:6650-6661.

Uchimura N, Cherubini E, North RA (1989).  Inward rectification
in rat nucleus accumbens neurons. J Neurophysiol 62, 1280-1286.

Kubo Y, Murata Y (2001).  Control of rectification and permeation by two
distinct sites after the second transmembrane region in Kir2.1 K+
channel. J Physiol 531, 645-660.

Hayashi H, Fishman HM (1988). Inward rectifier K+ channel kinetics from
analysis of the complex conductance of aplysia neuronal membrane.
Biophys J 53, 747-757. 

Jason Moyer 2004 jtmoyer@seas.upenn.edu
ENDCOMMENT


UNITS {
        (mA) = (milliamp)
        (mV) = (millivolt)
        (S)  = (siemens)
        (molar) = (1/liter)
        (mM) = (millimolar)
}
 
NEURON {
        SUFFIX kir
        USEION k READ ek WRITE ik
        RANGE  gkbar, ik, mvhalf, mslope, mshift, qfact
}
 
PARAMETER {
	gkbar  = 0.00015 		(S/cm2)	: 

	mvhalf = -52		(mV)	: fit to Hayashi 1988 fig 14; minf = alpha/(alpha+beta)
	mslope = 13		(mV)	: fit to Hayashi 1988 fig 14
	mshift = 30			(mV)	: fit to Kubo 2001 fig 2B left - with ek = -84.3,
						:  mshift can range from 20 to 30 to fit slope of IR
	qfact = 0.5				: match in vitro data
}
 
STATE { m }
 
ASSIGNED {
		ki				(mM)
		ko				(mM)
        v 				(mV)
        ik 				(mA/cm2)
        gk				(S/cm2)
        minf		
        ek				(mV)
   }
 
BREAKPOINT {
        SOLVE state METHOD cnexp
        gk = gkbar * m
        ik = gk * ( v - ek )
}
  
INITIAL {
	rates(v)
	m = minf
}

FUNCTION_TABLE taumkir (v(mV))  (ms)		: Hayashi

DERIVATIVE state { 
        rates(v)
        m' = (minf - m) / ( taumkir(v)/qfact )
}
 
PROCEDURE rates( v(mV) ) {  : Boltzman adjusted to give proper Erev dependency 
	TABLE minf DEPEND mvhalf, mshift, mslope
		FROM -200 TO 200 WITH 201
			minf = 1  /  ( 1 + exp( (v - mvhalf + mshift) / mslope) )
}