Striatal Spiny Projection Neuron, inhibition enhances spatial specificity (Dorman et al 2018)

 Download zip file 
Help downloading and running models
We use a computational model of a striatal spiny projection neuron to investigate dendritic spine calcium dynamics in response to spatiotemporal patterns of synaptic inputs. We show that spine calcium elevation is stimulus-specific, with supralinear calcium elevation in cooperatively stimulated spines. Intermediate calcium elevation occurs in neighboring non-stimulated dendritic spines, predicting heterosynaptic effects. Inhibitory synaptic inputs enhance the difference between peak calcium in stimulated spines, and peak calcium in non-stimulated spines, thereby enhancing stimulus specificity.
1 . Dorman DB, Jedrzejewska-Szmek J, Blackwell KT (2018) Inhibition enhances spatially-specific calcium encoding of synaptic input patterns in a biologically constrained model. Elife, Kennedy, Mary B, ed. [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: Basal ganglia;
Cell Type(s): Neostriatum spiny neuron;
Channel(s): Ca pump; Kir; I A; I A, slow; I CAN; I K,Ca; I Krp; I Na,t; I L high threshold; I R; I T low threshold; IK Bkca; IK Skca; Na/Ca exchanger;
Gap Junctions:
Receptor(s): AMPA; NMDA; GabaA;
Gene(s): Cav3.2 CACNA1H; Cav3.3 CACNA1I; Cav1.2 CACNA1C; Cav1.3 CACNA1D; Cav2.2 CACNA1B; Kv4.2 KCND2; Kir2.1 KCNJ2; Kv2.1 KCNB1;
Transmitter(s): Gaba; Glutamate;
Simulation Environment: GENESIS;
Model Concept(s): Calcium dynamics; Detailed Neuronal Models; Synaptic Integration; Synaptic Plasticity;
Implementer(s): Dorman, Daniel B ;
Search NeuronDB for information about:  GabaA; AMPA; NMDA; I Na,t; I L high threshold; I T low threshold; I A; I K,Ca; I CAN; I A, slow; Na/Ca exchanger; I Krp; I R; Ca pump; Kir; IK Bkca; IK Skca; Gaba; Glutamate;

/***************************		MS Model, Version 12 *********************

	Avrama Blackwell
	Wonryull Koh
	Rebekah Evans

    str  CalciumName = "Ca_difshell_"
    str  bufferLT = "Ca_pool_LT"     // L and T type channels
    str  bufferNR = "Ca_pool_NR"     // coupled to the other channels (N and R)
    str  bufferAll = "Ca_pool_all"     // all calcium channels

	int calciumdye = 0//2 //  flags for cacium dye. "0" means NO calcium dyes.
                     // 1= Fura-2 (default conc 100 uM, can change below) - not defined in spines.g for calciumtype=1
                     // 3= Fluo4 
                     // 2= Fluo-5F (300uM for Shindou, 100uM for Sabatini (check) and Lovinger)
                     // 4 = Fluo4FF
	int calciumtype = 0     // we  have two types of calcium:
                     //  0 : detailed multi-shell model, using "difshell" object
                     //  1 : simple calcium pool adopted from Sabatini's 2001, 2004
	int calciuminact = 1 //calcium dependent inactivation of calcium channels, CaL1.2 and 1.3
		//0 = no CDI
		//1 = CDI for 1.3 and 1.2 N and R
	float cdiqfact = 1

float Ca_basal = 50e-6 //50nM

float outershell_thickness = 0.1e-6 //outermostshell thickness
float thicknessincrease=2.0 //perhaps only 1.5, set to 1 for no increase
float minthick=1.1*outershell_thickness	

float dca = 200.0e-12 //200 (um^2)(s^(-1))
//dca = 0.1*dca

//buffer variables [Kim et al 2010 (J Neurosci)]
str bname1 = "calbindin"
if (calciumdye == 0)
    float btotal1 = 80.0e-3 	//4 * 40 uM total
    float btotal1 = 0 //If you don't dialize calbindin, soma Ca is too low (Kerr and Plenz 2008)

float kf1 =  0.028e6 //0.028 (nM^(-1))(s^(-1))  
float kb1 = 19.6 //19.6 (s^(-1))
float d1 = 66e-12 // See what happens if changed to 11e-12

str bname2 = "CaMC"
if (calciumdye == 0)
	float btotal2 = 15.0e-3 	//was 30.0e-3, but Rodrigo's paper seems to have about half the CaM as Myungs.
	float btotal2 = 0.0e-3		//CaM is 'dialyzed' when there is a calcium dye present
float kf2 =  0.006e6 //0.006 (nM^(-1))(s^(-1))  
float kb2 = 9.1 //9.1 (s^(-1))
float d2 = 66.0e-12// 11 ((um)^2)(s^(-1)) // Waxham, MN 2008 Biophysical Journal

str bname4 = "CaMN" //Ca4? in Kim et al. 2011
if (calciumdye == 0)
	float btotal4 = 15.0e-3 	//was 30.0e-3, but Rodrigo's paper seems to have about half the CaM as Myungs.
	float btotal4 = 0.0e-3		//CaM is 'dialyzed' when there is a calcium dye present
float kf4 =  0.1e6 //0.1 (nM^-1)(s^-1)
float kb4 = 1000 // (s^(-1))
float d4 = 66.0e-12 // Waxham, MN 2008 Biophysical Journal

str bname3 = "Fura-2"  //parameters fall within ranges given in  deshutter's book chapter in Methods in Neuronal Modeling 
float btotal3 = 100e-3 	//100uM?  Kerr uses 100? 
float kf3 =  1000e3//100e3 //1000e3  // 1e5(mM^(-1))(s^(-1))  (deschutter range: 0.25-6e8 M-1sec-1) (25e3 to 6e5 mM-1sec-1) kb kf ratio 185nM (0.000185) 
float kb3 = 185//18.5 //185 //(s^(-1))  17-380 s^-1 range given in deShutter's chapter(methods in neuronal modeling)
float d3 = 6e-11 //((m)^2)(s^(-1)) (deschutter range: 0.4e-11 m^2sec-1 to 2e-10 m^2sec-1) 6e-11 based on Young's eqn and a viscossity of 4.1, eqn is in Rodrigo's EPAC paper

str bname5 = "Fluo5F" 
float btotal5 = 300.0e-3 //Shindou and Wickens use 300uM, Lovinger will use 100uM
float kf5 = 2.36e5 // (mM^-1)(s^-1) (2.36e8 M^-1 sec^-1, from Zenisek et al., 2003 kd=2.3uM) 
float kb5 = 542.8 //pe sec, for kb/kf=Kd=2.3uM (0.0023 mM) from Shindou 2011
float d5 = 6e-11 //mol weight similar to Fura2, using same dif constants.  

str bname6 = "Fluo4"
float btotal6 = 200e-3 //Plotkin use 100uM or 200
float kf6 = 2.36e5 //(mM^-1s^-1) Escobar et al 1997, on rate for Fluo3, which seems to be really similar to Fluo4
float kb6 = 82.6//s^-1, Fluo4 kd is 0.35 uM
float d6 = 6e-11 //mol weight similar to Fluo-5f, using same dif constants.

str bname7 = "Fluo4FF"
float btotal7 = 500e-3 //500 uM used by Plotkin
float kf7 = 0.8e5//412e3//412uM^-1s^-1 from Mehta et al 2014; 0.8e5 mM^-1s^-1 from 0.8e8/M/s from Figueroa et al 2012
float kb7 = 776//4000 //4000 per sec, from Mehta et al 2014; 776 per sec from Figueroa et al 2012; KDd=9.7uM
float d7 = 6e-11

//endogenous immobile low affinity buffer (e.g. see Matthews, Scoch, & Dietrich, J. Neuro, 2013 (hippocampus))
str bname8 = "FixedBuffer"
float btotal8 = 2.5//4.5//1//3 //4.5  //4500 uM Calculated based on Matthews et al 2013 and Carter and Sabatini 2004 assumes mobile buffer completely washed out 
float kf8 = {0.4e6} // 0.4 uM^-1 ms^-1 from Matthews et al 2013
float kb8 = {40e3}//20e3//40e3:kD=100uM; 20e3:kD = 50uM from Matthews et al 2013 
float d8 = 0 //immobile

if (calciumdye==1)
    float btotalfluor={btotal3}
    float kffluor={kf3}
    float kbfluor={kb3}
    str bnamefluor={bname3}
    float dfluor={d3}
elif (calciumdye==2)
    float btotalfluor={btotal5}
    float kffluor={kf5}
    float kbfluor={kb5}
    str bnamefluor={bname5}
    float dfluor={d5}
elif (calciumdye==4)
    float btotalfluor={btotal7}
    float kffluor={kf7}
    float kbfluor={kb7}
    str bnamefluor={bname7}
    float dfluor={d7}

elif (calciumdye==3)
    float btotalfluor={btotal6}
    float kffluor={kf6}
    float kbfluor={kb6}
    str bnamefluor={bname6}
    float dfluor={d6}

//kcat & km for MMPump
float km = 0.3e-3
str MMpumpName= "MMpump"
float kcatsoma = 85e-8  //75 pmol ((cm)^(-2)) (s^(-1)) //Markram et al 1998
float kcatdend = 8e-8 //12e-8	

//kcat & km for NCX
//not yet used in dendrites
float kmNCX=1e-3
float kcatNCX=0
str NCXname="NCX"

float iCaLeakKluge = 2 // offset the effect of LVA calcium window currents at rest on calcium concentration to maintain basal calcium (used in CaDifshell.g)