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|Section2= |Section3= |Section4= }} ''N''-Acetylaspartic acid, or ''N''-acetylaspartate (NAA), is a derivative of aspartic acid with a formula of C6H9NO5 and a molecular weight of 175.139. NAA is the second-most-concentrated molecule in the brain after the amino acid glutamate. It is detected in the adult brain in neurons, oligodendrocytes, and myelin and is synthesized in the mitochondria from the amino acid aspartic acid and acetyl-coenzyme A.〔Patel, T. B. and J. B. Clark (1979). "Synthesis of N-acetyl-L-aspartate by rat brain mitochondria and its involvement in mitochondrial/cytosolic carbon transport." Biochem J 184(3): 539-46. http://www.ncbi.nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db=PubMed&dopt=Citation&list_uids=540047〕 The various functions served by NAA are still under investigation, but the primary proposed functions include its being: # A neuronal osmolyte that is involved in fluid balance in the brain # A source of acetate for lipid and myelin synthesis in oligodendrocytes, the glial cells that myelinate neuronal axons # A precursor for the synthesis of the important neuronal dipeptide N-Acetylaspartylglutamate # A contributor to energy production from the amino acid glutamate in neuronal mitochondria. In the brain, NAA is thought to be present predominantly in neuronal cell bodies, where it acts as a neuronal marker. However, the recent discovery of a higher concentration of NAA in myelin and oligodendrocytes than in neurons raises questions about the validity of the use of NAA as a neuronal marker.〔 NAA gives off the largest signal in magnetic resonance spectroscopy of the human brain, and the levels measured there are decreased in numerous neuropathological conditions ranging from brain injury to stroke to Alzheimer's disease. This fact makes NAA a reliable diagnostic molecule for doctors treating patients with brain damage or disease. NAA may also be a marker of creativity.〔http://www.newscientist.com/article/mg20227084.300-creativity-chemical-favours-the-smart.html〕 It has also been demonstrated that high NAA level in hippocampus is related to better working memory performance in humans.〔Kozlovskiy, S, Vartanov, A, Pyasik, M, Polikanova, I. (2012). "Working memory and N-acetylaspartate level in hippocampus, parietal cortex and subventricular zone". ''International Journal of Psychology'', vol. 47. P. 584. 〕 NAA may function as a neurotransmitter in the brain by acting on metabotropic glutamate receptors. ==See also== * Aspartoacylase * Canavan disease 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「N-Acetylaspartic acid」の詳細全文を読む スポンサード リンク
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