N-Acetylaspartylglutamic acid

N-Acetylaspartylglutamic acid

Names
Other names 2-[(2-Acetamido-4-hydroxy-4-oxobutanoyl)amino]pentanedioic acid N-Acetyl-L-α-aspartyl-L-glutamic acid N-Acetyl-1-aspartylglutamic acid Spaglumic acid
Identifiers
CAS Number	3106-85-2 N
3D model (JSmol)	Interactive image
Abbreviations	NAAG
ChemSpider	164080 Y
ECHA InfoCard	100.163.604
MeSH	N-acetyl-1-aspartylglutamic+acid
PubChem CID	188803
UNII	X81L78B3RB N
InChI InChI=1S/C11H16N2O8/c1-5(14)12-7(4-9(17)18)10(19)13-6(11(20)21)2-3-8(15)16/h6-7H,2-4H2,1H3,(H,12,14)(H,13,19)(H,15,16)(H,17,18)(H,20,21)/t6-,7-/m0/s1 Y Key: OPVPGKGADVGKTG-BQBZGAKWSA-N Y
SMILES CC(=O)N[C@@H](CC(O)=O)C(=O)N[C@@H](CCC(O)=O)C(O)=O
Properties
Chemical formula	C11H16N2O8
Molar mass	304.26 g·mol−1
Pharmacology
ATC code	R01AC05 (WHO) S01GX03 (WHO)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

N-Acetylaspartylglutamic acid (N-acetylaspartylglutamate or NAAG) is a peptide neurotransmitter and the third-most-prevalent neurotransmitter in the mammalian nervous system. NAAG consists of N-acetylaspartic acid (NAA) and glutamic acid coupled via a peptide bond.

NAAG was discovered as a nervous system-specific peptide in 1965 by Curatolo and colleagues but initially disregarded as a neurotransmitter and not extensively studied. However it meets the criteria for a neurotransmitter, including being concentrated in neurons, packed in synaptic vesicles, released in a calcium-dependent manner, and hydrolyzed in the synaptic space by enzymatic activity.

NAAG activates a specific receptor, the metabotropic glutamate receptor type 3. It is synthesized enzymatically from its two precursors and catabolized by NAAG peptidases in the synapse. The inhibition of the latter enzymes has potentially important therapeutic effects in animal models of several neurologic conditions and disorders.

Under the INN spaglumic acid, NAAG is used as an antiallergic medication in eye drops and nasal preparations.

After its discovery in 1965, NAAG was disregarded as a neurotransmitter for several reasons. First, neuropeptides were not considered neurotransmitters until years later. Second, it did not seem to directly affect membrane potential, so it was classified as a metabolic intermediate. The importance of brain peptides became clearer with the discovery of endogenous opioids. Whereas the ability of NAAG to interact with NMDA receptors in a manner relevant to physiology is controversial, its primary receptor was long believed to be the mGluR3. Its interaction with the mGluR3 causes an activation of G proteins that reduce the concentration of the second messengers cAMP and cGMP in the both nerve cells and glia. This can lead to several changes in the cellular activity, including regulation of gene expression, reduction in the release of transmitter, and inhibition of long-term potentiation. Stimulation of the mGluR3 by NAAG has been, however, questioned, finding relevant glutamate contamination in commercially available NAAG.