Gamma-aminobutyric acid (GABA) peak
Citation, DOI & article data
Gamma-aminobutyric acid (GABA), produced by the decarboxylation of glutamate 4, is the principle inhibitory neurotransmitter in the central nervous system 1 and as such, is one of the compounds examined in MR spectroscopy. It is present in the human brain at a concentration of about 1 mM, a whole order of magnitude lower than some of the more abundantly present metabolites. GABA resonates at approximately 2.2-2.4 ppm chemical shift, overlapping the peaks of the more abundant metabolites N-acetylaspartate (NAA), creatine (Cr), and glutamate-glutamine (Glx) 1-3. Therefore, it is not routinely possible to separate it from the other peaks in this region of the spectrum.
Changes in concentration of GABA have been reported in a number of clinical scenarios, although day-to-day application is limited 2:
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