title: 13C magnetic resonance spectroscopy studies of alterations in glutamate neurotransmission.
abstract: Over the past a few years, significant progress has been made in refining the in vivo 13C magnetic resonance spectroscopy technique and in applying it to studying the alterations in the glutamate-glutamine cycling flux. Meanwhile, the details of the metabolic modeling are being rigorously debated. Recent evidence against fast alpha-ketoglutarate-glutamate exchange across the mitochondrial membrane is examined. Previous reports have indicated that glutamate release or 13C label incorporation into glutamine is attenuated at elevated concentrations of endogenous gamma-aminobutyric acid (GABA). A recent study has shown that phenelzine administration reduces the glutamate-glutamine cycling flux while raising endogenous GABA levels in vivo. Effects of several metabotropic glutamate receptor agonists and antagonists and brain disorders on the glutamate-glutamine cycle are also summarized.
authors.affiliation: Molecular Imaging Branch, Mood and Anxiety Disorders Program, National Institute of Mental Health, Bethesda, Maryland 20892-1527, USA. shenj@intra.nimh.nih.gov
authors.forename: Jun
authors.initials: J
authors.lastname: Shen
mesh_terms: D001786:Blood Glucose / Q000378:metabolism; D001921:Brain / Q000502:physiology*; D005971:Glutamates / Q000378:metabolism; D018698:Glutamic Acid / Q000378:metabolism*; D005973:Glutamine / Q000378:metabolism; D006801:Humans; D009682:Magnetic Resonance Spectroscopy; D009457:Neuroglia / Q000502:physiology; D009474:Neurons / Q000502:physiology; D018094:Receptors, Metabotropic Glutamate / Q000502:physiology; D009435:Synaptic Transmission / Q000502:physiology*; D005680:gamma-Aminobutyric Acid / Q000378:metabolism
chemical_list: D001786:Blood Glucose; D005971:Glutamates; D018094:Receptors, Metabotropic Glutamate; C088956:alpha-ketoglutamic acid; D005973:Glutamine; D018698:Glutamic Acid; D005680:gamma-Aminobutyric Acid