Corticosterone facilitates hippocampal glutamate transmission, but the cellular pathways by which AMPA receptor (AMPAR) signaling is adjusted remain elusive. Single quantum-dot imaging in live rat hippocampal neurons revealed that corticosterone triggers, via distinct corticosteroid receptors, time-dependent increases in GluR2-AMPAR surface mobility and synaptic surface GluR2 content. Furthermore, corticosterone potentiates the increase of synaptic surface GluR2 contents by a chemical long-term potentiation stimulus, revealing the influence that corticosterone has on AMPAR trafficking.