AP5

AP5 or APV ((2R)-amino-5-phosphonovaleric acid; (2R)-amino-5-phosphonopentanoate) is a selective NMDA receptor antagonist that competitively inhibits the ligand (glutamate) binding site of NMDA receptors.^[1]

AP5 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.

In general, AP5 is very fast-acting within in vitro preparations, and can block NMDA receptor action at a reasonably small concentration. The active isomer of AP5 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.

AP5 can block the conversion of a silent synapse to an active one, since this conversion is NMDA receptor-dependent.

AP5 was developed by Jeff Watkins and Harry Olverman.

See also

• AMPA
• AP7 (drug)
• Kainate

References

1. ^ Morris RG. Synaptic plasticity and learning: selective impairment of learning rats and blockade of long-term potentiation in vivo by the N-methyl-D-aspartate receptor antagonist AP5. Journal of Neuroscience. 1989 Sep;9(9):3040-57. PMID 2552039

• Cellular Analog of Differential Classical Conditioning in Aplysia: Disruption by the NMDA Receptor Antagonist DL-2-Amino-5-Phosphonovalerate

^ Laube, B; Hirai H, Sturgess M, Betz H, and Kuhse J (1997). "Molecular determinants of antagonists discrimination by NMDA receptor subunits: Analysis of the glutamate binding site on the NR2B subunit". Neuron 18 (3): 493–503. doi:10.1016/S0896-6273(00)81249-0. PMID 9115742.