| 词条 | N-Methyl-D-aspartic acid |
| 释义 |
| Watchedfields = changed | verifiedrevid = 312363528 | Name = N-Methyl-D-aspartic acid | ImageFile = NMDA.svg | ImageFile_Ref = {{chemboximage|correct|??}} | ImageSize = 160 | ImageName = Stereo, skeletal formula of N-methyl-D-aspartic acid | ImageFile1 = NMDA2.png | ImageFile1_Ref = {{chemboximage|correct|??}} | ImageSize1 = 160 | ImageName1 = Ball and stick model of N-methyl-D-aspartic acid | ImageFile2 = NMDA spacefill.png | ImageFile2_Ref = {{chemboximage|correct|??}} | ImageSize2 = 160 | ImageName2 = Spacefill model of N-methyl-D-aspartic acid | IUPACName = (2R)-2-(Methylamino)butanedioic acid[1] | OtherNames = N-Methylaspartate; N-Methyl-D-aspartate; NMDA |Section1={{Chembox Identifiers | IUPHAR_ligand = 4268 | CASNo = 6384-92-5 | CASNo_Ref = {{cascite|correct|??}} | PubChem = 22880 | ChemSpiderID = 21436 | ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}} | KEGG = C12269 | KEGG_Ref = {{keggcite|correct|kegg}} | MeSHName = N-Methylaspartate | ChEBI = 31882 | ChEBI_Ref = {{ebicite|correct|EBI}} | ChEMBL = 291278 | ChEMBL_Ref = {{ebicite|correct|EBI}} | RTECS = CI9457000 | Beilstein = 1724431 | SMILES = CN[C@H](CC(=O)O)C(=O)O | StdInChI = 1 S/C5H9NO4/c1-6-3(5(9)10)2-4(7)8/h3,6H,2H2,1H3,(H,7,8)(H,9,10)/t3-/m1/s1 | StdInChIKey = HOKKHZGPKSLGJE-GSVOUGTGSA-N |Section2={{Chembox Properties | C=5 | H=9 | N=1 | O=4 | Appearance = White, opaque crystals | Odor = Odorless | MeltingPtC = 189 to 190 | LogP = 1.39 | pKa = 2.206 | pKb = 11.791 |Section3={{Chembox Hazards | SPhrases = {{S22}}, {{S24/25}} | LD50 = 137 mg kg−1 (intraperitoneal, mouse) |Section4={{Chembox Related | OtherFunction_label = amino acid derivatives | OtherFunction = {{unbulleted list|Sarcosine|Dimethylglycine|beta-Methylamine-L-alanine}} | OtherCompounds = Dimethylacetamide }} N-Methyl-D-aspartic acid or N-Methyl-D-aspartate (NMDA) is an amino acid derivative that acts as a specific agonist at the NMDA receptor mimicking the action of glutamate, the neurotransmitter which normally acts at that receptor. Unlike glutamate, NMDA only binds to and regulates the NMDA receptor and has no effect on other glutamate receptors (such as those for AMPA and kainate). NMDA receptors are particularly important when they become overactive during withdrawal from alcohol as this causes symptoms such as agitation and, sometimes, epileptiform seizures. Biological functionNMDA is a water-soluble synthetic substance that is not normally found in biological tissue. It was first synthesized in the 1960s. NMDA is an excitotoxin (it kills nerve cells by over-exciting them); 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. However, in lower quantities NMDA is not neurotoxic. In fact, normal operation of the NMDA receptor allows individuals to respond to excitatory stimuli through the interrelated functioning of NMDA receptors, glutamate, and dopamine. Therefore, the action of glutamate specifically through NMDA receptors can be investigated by injecting small quantities of NMDA into a certain region in the brain: for example, injection of NMDA in a brainstem region induces involuntary locomotion in cats and rats. The mechanism of action for the NMDA receptor is a specific agonist binding to its NR2 subunits, and then a non-specific cation channel is opened, which can allow the passage of Ca2+ and Na+ into the cell and K+ out of the cell. The excitatory postsynaptic potential (EPSP) produced by activation of an NMDA receptor also increases the concentration of Ca2+ in the cell. The Ca2+ can in turn function as a second messenger in various signaling pathways.[2][3][4][5] This process is modulated by a number of endogenous and exogenous compounds and plays a key role in a wide range of physiological (e.g. memory) and pathological processes (e.g. Excitotoxicity). {{clear left}}Antagonists{{main|NMDA receptor antagonist}}Examples of antagonists of the NMDA receptor are APV, amantadine, dextromethorphan (DXM), ketamine, magnesium,[6] tiletamine, phencyclidine (PCP), riluzole, memantine, methoxetamine (MXE), methoxphenidine (MXP) and kynurenic acid; the latter is the only known endogenous antagonist. They are commonly referred to as NMDA receptor antagonists. See also
References1. ^{{cite web|title=N-Methylaspartate - Compound Summary|url=https://pubchem.ncbi.nlm.nih.gov/summary/summary.cgi?cid=22880&loc=ec_rcs|work=PubChem Compound|publisher=National Center for Biotechnology Information|accessdate=9 January 2012|location=USA|date=24 June 2005|at=Identification}} 2. ^{{cite journal|last=Dingledine|first=R|author2=Borges K|title=The glutamate receptor ion channels|journal=Pharmacol. Rev.|date=Mar 1999|volume=51|issue=1|pages=7–61|pmid=10049997}} 3. ^{{cite journal|last=Liu|first=Y|author2=Zhang J|title=Recent development in NMDA receptors|journal=Chin Med J (Engl)|date=Oct 2000|volume=113|issue=10|pages=948–56|pmid=11775847}} 4. ^{{cite journal|last=Cull-Candy|first=S|author2=Brickley S|title=NMDA receptor subunits: diversity, development and disease|journal=Current Opinion in Neurobiology|date=Jun 2001|volume=11|issue=3|pages=327–35|pmid=11399431|doi=10.1016/S0959-4388(00)00215-4}} 5. ^{{cite journal|last=Paoletti|first=P|author2=Neyton J|title=NMDA receptor subunits: function and pharmacology|journal=Current Opinion in Pharmacology|date=Feb 2007|volume=7|issue=1|pages=39–47|pmid=17088105|doi=10.1016/j.coph.2006.08.011|url=https://hal.archives-ouvertes.fr/hal-00115220/document}} 6. ^{{Cite journal|last=Murck|first=H.|date=2002-01-01|title=Magnesium and Affective Disorders|journal=Nutritional Neuroscience|volume=5|issue=6|pages=375–389|doi=10.1080/1028415021000039194|issn=1028-415X|pmid=12509067}} Further reading
4 : Neurotransmitters|Dicarboxylic acids|Amino acid derivatives|Glutamate (neurotransmitter) |
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