Activation induced changes in GABA: Functional MRS at 7 T with MEGA-sLASER

作者：Chen Chen^*; Sigurdsson Hilmar P; Pepes Sophia E; Auer Dorothee P; Morris Peter G; Morgan Paul S; Gowland Penny A; Jackson Stephen R

来源：NeuroImage, 2017, 156: 207-213.

DOI：10.1016/j.neuroimage.2017.05.044

• GABA
• MEGA editing
• Functional MRS
• Motor cortex
• 7T

Functional magnetic resonance spectroscopy (fMRS) has been used to assess the dynamic metabolic responses of the brain to a physiological stimulus non-invasively. However, only limited information on the dynamic functional response of gamma-aminobutyric acid (GABA), the primary inhibitory neurotransmitter in the brain, is available. We aimed to measure the activation-induced changes in GABA unambiguously using a spectral editing method, instead of the conventional direct detection techniques used in previous fMRS studies. The Mescher-Garwood-semi-localised by adiabatic selective refocusing (MEGA-sLASER) sequence was developed at 7 T to obtain the time course of GABA concentration without macromolecular contamination. A significant decrease (-12 +/- 5%) in the GABA to total creatine ratio (GABA/tCr) was observed in the motor cortex during a period of 10 min of hand-clenching, compared to an initial baseline level (GABA/tCr = 0.11 +/- 0.02) at rest. An increase in the Glx (glutamate and glutamine) to tCr ratio was also found, which is in agreement with previous findings. In contrast, no significant changes in NAA/tCr and tCr were detected. With consistent and highly efficient editing performance for GABA detection and the advantage of visually identifying GABA resonances in the spectra, MEGA-sLASER is demonstrated to be an effective method for studying of dynamic changes in GABA at 7 T.

• 出版日期2017-8-1