TY - JOUR T1 - Proton MR Spectroscopy–Detectable Major Neurotransmitters of the Brain: Biology and Possible Clinical Applications JF - American Journal of Neuroradiology JO - Am. J. Neuroradiol. DO - 10.3174/ajnr.A2587 AU - N. Agarwal AU - P.F. Renshaw Y1 - 2011/12/29 UR - http://www.ajnr.org/content/early/2011/12/29/ajnr.A2587.abstract N2 - SUMMARY: Neurotransmitters are chemical substances that, by definition, allow communication between neurons and permit most neuronal-glial interactions in the CNS. Approximately 80% of all neurons use glutamate, and almost all interneurons use GABA. A third neurotransmitter, NAAG, modulates glutamatergic neurotransmission. Concentration changes in these molecules due to defective synthetic machinery, receptor expression, or errors in their degradation and metabolism are accepted causes of several neurologic disorders. Knowledge of changes in neurotransmitter concentrations in the brain can add useful information in making a diagnosis, helping to pick the right drug of treatment, and monitoring patient response to drugs in a more objective manner. Recent advances in 1H-MR spectroscopy hold promise in providing a more reliable in vivo detection of these neurotransmitters. In this article, we summarize the essential biology of 3 major neurotransmitters: glutamate, GABA, and NAAG. Finally we illustrate possible applications of 1H-MR spectroscopy in neuroscience research. Abbreviations ADAlzheimer diseaseALSamyotrophic lateral sclerosisAMPARα-amino-3-hydroxyl-5-methyl-4-isoxazole-propionate receptorsATPadenosine triphosphateCNScentral nervous systemCrcreatineEAATexcitatory amino acid transporterEEGelectroencephalography18FDG-PET[18F]fluorodeoxyglucose–positron-emission tomographyGABAγ-aminobutyric acidGLASTglutamate/aspartate transporter1H-MRproton MRNAAN-acetylaspartateNAAGN-acetyl aspartylglutamateNMDARN-methyl D-aspartatePAGphosphate-activated glutaminasePDParkinson disease ER -