The model represents the role of different postsynaptic syntaxins in regulating neurotransmitter receptor dynamics. Despite being mostly concentrated at presynaptic terminals, Stx-1 has been suggested to play a role in regulating constitutive exocytosis of GABAARs, AMPARs and GluN2B-containing NMDA receptors. Interestingly, GluN2A-containing NMDARs insertion may depend on Stx-4, a non-complexin Stx isoform that also mediates AMPAR exocytosis during homeostatic plasticity. In contrast Stx-3, a complexin-binding isoform is the primary regulator of AMPAR exocytosis during NMDAR-dependent LTP. These results suggest dendritic membranes may contain microdomains enriched with different Stx isoforms which define specific regions for postsynaptic receptor exocytosis.