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NMDA
IUPAC name	N-methyl-D-aspartic acid
Identifiers
CAS number	[6384-92-5]
PubChem	22880
MeSH	NMDA
Properties
Molecular formula	C5H9N1O4
Molar mass	147.13 D
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

NMDA (N-methyl-D-aspartic acid) is an amino acid derivative acting as a specific agonist at the NMDA receptor, and therefore mimics the action of the neurotransmitter glutamate on that receptor. In contrast to glutamate, NMDA binds to and regulates the above receptor only, but not other glutamate receptors.

NMDA is a water-soluble synthetic substance that is not normally found in biological tissue. It was first synthesized in the 1960's. NMDA is an excitotoxin; this trait has applications in behavioral neuroscience research. The body of work utilizing this technique falls under the term "lesion studies." Researchers apply NMDA to specific regions of an (animal) subject's brain or spinal cord and subsequently test for the behavior of interest, such as operant behavior. If the behavior is compromised, it suggests the destroyed tissue was part of a brain region that made an important contribution to the normal expression of that behavior.

Contents 1 Antagonists 2 Forms 3 Implications for memory 4 References 5 Bibliography

Examples of antagonists of the NMDA receptor are APV, dextromethorphan, ketamine, phencyclidine (PCP), riluzole, and memantine. They are commonly referred to as NMDA receptor antagonists.

The structural formula of NMDA pictured above is written down as the neutral form. At physiological pH both carboxyl groups are deprotonated

When NMDA receptors are activated, they allow both sodium and calcium ions to enter the postsynaptic neuron. The calcium ions induce long-term changes in the postsynaptic membrane that make it more sensitive to synaptic input. This long-term potentiation may be a rudimentary component of memory.

Dr. Joe Tsien of Princeton University genetically engineered mice so that their NMDA receptors had a slightly altered structure and were activated for a longer time whenever they bound to a molecule of glutamate. These mice learned tasks better, ran mazes faster, and remembered the mazes longer than normal mice.

• Watkins J, Jane D. "The glutamate story". Br J Pharmacol 147 Suppl 1: S100-8. PMID 16402093. 

• Heinricher MM, Schouten JC, Jobst EE. (2001). Activation of brainstem N-methyl-D-aspartate receptors is required for the analgesic actions of morphine given systemically. Pain (2001) 92(1-2):129-138. PMID 11323134

• Mathias-Costa Blaise, Ramanathan Sowdhamini, Metpally Raghu Prasad Rao and Nithyananda Pradhan (2004). "Evolutionary trace analysis of ionotropic glutamate receptor sequences and modeling the interactions of agonists with different NMDA receptor subunits.". J. Mol. Model. 10(5-6): 305-16. PMID 15597199.