Ifenprodil

Ifenprodil is an inhibitor of the NMDA receptor, specifically of GluN1 (glycine-binding NMDA receptor subunit 1) and GluN2B (glutamate-binding NMDA receptor subunit 2) subunits. Additionally, ifenprodil inhibits GIRK channels, and interacts with alpha1 adrenergic, serotonin, and sigma receptors.

NMDA receptors are multimeric ionotropic glutamate receptors composed of four subunits. GluN1 is obligate for functional expression. Other subunits include GluN2A, GluN2B, and the more recently discovered GluN3 subunits. Ifenprodil selectively blocks NMDA receptors containing the GluN2B subunit.