Endocannabinoid dynamics gate spike-timing dependent depression and potentiation (Cui et al 2016)

 Download zip file 
Help downloading and running models
Accession:187605
The endocannabinoid (eCB) system is considered involved in synaptic depression. Recent reports have also linked eCBs to synaptic potentiation. However it is not known how eCB signaling may support such bidirectionality. To question the mechanisms of this phenomena in spike-timing dependent plasticity (STDP) at corticostriatal synapses, we combined electrophysiology experiments with biophysical modeling. We demonstrate that STDP is controlled by eCB levels and dynamics: prolonged and moderate levels of eCB lead to eCB-mediated long-term depression (eCB-tLTD) while short and large eCB transients produce eCB-mediated long-term potentiation (eCB-tLTP). Therefore, just like neurotransmitters glutamate or GABA, eCB form a bidirectional system.
Reference:
1 . Cui Y, Prokin I, Xu H, Delord B, Genet S, Venance L, Berry H (2016) Endocannabinoid dynamics gate spike-timing dependent depression and potentiation. Elife 5:e13185 [PubMed]
Model Information (Click on a link to find other models with that property)
Model Type: Synapse; Channel/Receptor;
Brain Region(s)/Organism:
Cell Type(s): Neostriatum medium spiny direct pathway GABA cell; Neostriatum medium spiny indirect pathway GABA cell; Neostriatum spiny neuron;
Channel(s): I L high threshold; I Calcium; I_SERCA; I Cl, leak; Ca pump;
Gap Junctions:
Receptor(s): AMPA; NMDA; mGluR; Glutamate; IP3;
Gene(s):
Transmitter(s):
Simulation Environment: FORTRAN; Python;
Model Concept(s): Ion Channel Kinetics; Coincidence Detection; Parameter Fitting; Synaptic Plasticity; Long-term Synaptic Plasticity; Signaling pathways; STDP; Calcium dynamics; Parameter sensitivity; G-protein coupled; Neuromodulation;
Implementer(s):
Search NeuronDB for information about:  Neostriatum medium spiny direct pathway GABA cell; Neostriatum medium spiny indirect pathway GABA cell; AMPA; NMDA; mGluR; Glutamate; IP3; I L high threshold; I Calcium; I_SERCA; I Cl, leak; Ca pump;
!    -*- f95 -*-
! (c) 2016 - Ilya Prokin - isprokin@gmail.com - https://sites.google.com/site/ilyaprokin
! INRIA Rhone-Alpes
! STDP model : TRPV1 channel
! An implementation of the allosteric TRPV1 model by Matta & Ahern, 2007; Calcium flux modeled by GHK.

module TRPV1

    use pars_mod
    use ghk_flux

    implicit none

    contains

    ! Matta & Ahern, 2007 (their eq 3)
    real*8 function g_TRPV1_func(AEA,V,pars)
        implicit none
        real*8 :: AEA,V
        type(pars_type) :: pars
        real*8 :: L,D,C,P,K,Q,x,J
        !con0stants
        L=pars%TRPV1%L
        D=pars%TRPV1%D
        C=pars%TRPV1%C
        P=pars%TRPV1%P
        K=pars%TRPV1%K
        Q=AEA/pars%TRPV1%KD
        x=pars%TRPV1%z*pars%common%F*V/pars%common%RT
        if (x <= 85.0) then
            J=pars%TRPV1%J0*exp(x)
            g_TRPV1_func = 1/(1+(1+J+K+Q+J*K+J*Q+K*Q+J*K*Q)/(L*(1+J*D+K*C+Q*P+J*K*C*D+J*Q*D*P+K*Q*C*P+J*K*Q*D*C*P)))
        else
            g_TRPV1_func = 1/(1+(1+K+Q+K*Q)/(L*(D+K*C*D+Q*D*P+K*Q*D*C*P)))
        endif
    end function g_TRPV1_func

    real*8 function j_ca_TRPV1_func(g, V, calo, cali, pars)
        implicit none
        ! g = i/V
        real*8, intent(in) :: g, V, calo, cali
        type(pars_type), intent(in) :: pars
        j_ca_TRPV1_func = -pars%TRPV1%p_ca * g * ghk(V,cali,calo, pars)
    end function j_ca_TRPV1_func

end module TRPV1

Loading data, please wait...