In vivo detection of cortical GABA turnover from intravenously infused [1-13C]D-glucose

✍ Scribed by Jehoon Yang; Charles Q. Li; Jun Shen

• Book ID: 102532712
• Publisher: John Wiley and Sons
• Year: 2005
• Tongue: English
• Weight: 249 KB
• Volume: 53
• Category: Article
• ISSN: 0740-3194
• DOI: 10.1002/mrm.20473

✦ Synopsis

Abstract

In this study [2‐^13^C] γ‐aminobutyric acid (GABA) was spectrally resolved in vivo and detected simultaneously with [4‐^13^C]glutamate (Glu) and [4‐^13^C]glutamine (Gln) in the proton spectra obtained from a localized 40 μL voxel in rat neocortex with the use of an adiabatic ^1^H‐observed, ^13^C‐edited (POCE) spectroscopy method and an 89‐mm‐bore vertical 11.7 Tesla microimager. The time‐resolved kinetics of ^13^C label incorporation from intravenously infused [1‐^13^C]glucose into [4‐^13^C]Glu, [4‐^13^C]Gln, and [2‐^13^C]GABA were measured after acute administration of gabaculine, a potent and specific inhibitor of GABA‐transaminase. In contrast to previous observations of a rapid turnover of [2‐^13^C]GABA from [1‐^13^C]glucose in intact rat brain, the rate of ^13^C incorporation from [1‐^13^C]glucose into [2‐^13^C]GABA in the gabaculine‐treated rats was found to be significantly reduced as a result of the blockade of the GABA shunt. Magn Reson Med 53:1258–1267, 2005. Published 2005 Wiley‐Liss, Inc.