Presynaptic NMDA receptors: Are they dendritic receptors in disguise?

► Criteria for defining presynaptic receptors. ► Controversy surrounding locus of NMDA receptor expression. ► Novel methods for probing NMDA receptor function. ► Review of recent data demonstrating target-specific expression of presynaptic NMDA receptors. ► Discussion of the functional role of presynaptic NMDA receptors.