Abstract
In vivo magnetic resonance spectroscopy (MRS) is a noninvasive technique for the measurement
of the concentration and synthesis of metabolites in the brain. Application of the
state-of-the-art in vivo 13C and 15N MRS techniques to studying the synthesis of glutamate and glutamine has revealed
that the glutamate–glutamine cycle between neurons and glia is a major metabolic flux,
with a flux rate of 60%–80% relative to neuronal oxidative glucose metabolism in the
resting human cerebral cortex. The MRS studies leading to the quantification of the
glutamate–glutamine cycling flux are reviewed here. The advantages and limitations
of different strategies are also discussed.
Keywords
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Article info
Publication history
Accepted:
July 2,
2002
Received in revised form:
June 25,
2002
Received:
April 9,
2002
Identification
Copyright
© 2002 Society of Biological Psychiatry. Published by Elsevier Inc. All rights reserved.
