APV blocks the cellular analog of classical conditioning in the sea slug Aplysia californica, and has similar effects on Aplysia long-term potentiation, since NMDA receptors are required for both. It is sometimes used in conjunction with the calcium chelator BAPTA to determine whether NMDARs are required for a particular cellular process.
APV is generally very fast acting within in vitro preparations, and can block NMDA receptor action at a reasonably small concentration. The active isomer of APV is considered to be the D configuration, although many preparations are available as a racemic mixture of D- and L-isomers. It is useful to isolate the action of other glutamate receptors in the brain, i.e. AMPA and kainate receptors.
APV can block the conversion of a silent synapse to an active one, since this conversion is NMDA receptor-dependent.