title: Cannabinoid-mediated short-term plasticity in hippocampus.
abstract: Endocannabinoids (eCBs) modulate both excitatory and inhibitory neurotransmission in hippocampus via activation of pre-synaptic cannabinoid receptors. Here, we present a model for cannabinoid mediated short-term depression of excitation (DSE) based on our recently developed model for the equivalent phenomenon of suppressing inhibition (DSI). Furthermore, we derive a simplified formulation of the calcium-mediated endocannabinoid synthesis that underlies short-term modulation of neurotransmission in hippocampus. The simplified model describes cannabinoid-mediated short-term modulation of both hippocampal inhibition and excitation and is ideally suited for large network studies. Moreover, the implementation of the simplified DSI/DSE model provides predictions on how both phenomena are modulated by the magnitude of the pre-synaptic cell's activity. In addition we demonstrate the role of DSE in shaping the post-synaptic cell's firing behaviour qualitatively and quantitatively in dependence on eCB availability and the pre-synaptic cell's activity. Finally, we explore under which conditions the combination of DSI and DSE can temporarily shift the fine balance between excitation and inhibition. This highlights a mechanism by which eCBs might act in a neuro-protective manner during high neural activity.
authors.affiliation: Department of Computer Science, University of Cyprus, Nicosia, Cyprus, mzachariou@cs.ucy.ac.cy.
authors.forename: Margarita
authors.initials: M
authors.lastname: Zachariou
authors.forename: Rüdiger
authors.initials: R
authors.lastname: Thul
mesh_terms: D000818:Animals; D001703:Biophysics; D002186:Cannabinoids / Q000378:metabolism* / Q000494:pharmacology; D006624:Hippocampus / Q000166:cytology*; D006801:Humans; D008954:Models, Biological; D009473:Neuronal Plasticity / Q000187:drug effects / Q000502:physiology*
chemical_list: D002186:Cannabinoids