AMPA Receptor Trafficking in Homeostatic Synaptic Plasticity: Functional Molecules and Signaling Cascades

Figure 2

Activity-dependent homeostatic regulation of AMPAR synaptic localization. Under basal conditions, a stable level of AMPARs at postsynaptic surface is maintained by balanced trafficking processes of receptor insertion and internalization (middle). High synaptic activity can be detected by neurons, leading to enhanced receptor internalization and reduced surface receptor localization (left). Conversely, when neurons are treated by long-term activity deprivation, higher levels of AMPARs are expressed at postsynaptic surface via enhanced receptor insertion, including both GluA2-containing and GluA2-lacking receptors (Cp-AMPAR) (right). During homeostatic regulation, the number of NMDARs at postsynaptic surface is not significantly altered under either condition.