Affiliation:
1. M.R. Centre, Department of Physics, University of Nottingham, Nottingham, United Kingdom
2. MR Center, SINTEF-UNIMED, Trondheim, Norway
Abstract
Glial-neuronal interchange of amino acids was studied by13C nuclear magnetic resonance spectroscopy of brain extracts from fluoroacetate-treated mice that received [1,2-13C]acetate and [1-13C]glucose simultaneously. [13C]Acetate was found to be a specific marker for glial metabolism even with the large doses necessary for nuclear magnetic resonance spectroscopy. Fluoroacetate, 100 mg/kg, blocked the glial, but not the neuronal tricarboxylic acid cycles as seen from the13C labeling of glutamine, glutamate, and γ-aminobutyric acid. Glutamine, but not citrate, was the only glial metabolite that could account for the transfer of13C from glia to neurons. Massive glial uptake of transmitter glutamate was indicated by the labeling of glutamine from [1-13C]glucose in fluoroacetate-treated mice. The C-3/C-4 enrichment ratio, which indicates the degree of cycling of label, was higher in glutamine than in glutamate in the presence of fluoroacetate, suggesting that transmitter glutamate (which was converted to glutamine after release) is associated with a tricarboxylic acid cycle that turns more rapidly than the overall cerebral tricarboxylic acid cycle.
Subject
Cardiology and Cardiovascular Medicine,Neurology (clinical),Neurology
Cited by
151 articles.
订阅此论文施引文献
订阅此论文施引文献,注册后可以免费订阅5篇论文的施引文献,订阅后可以查看论文全部施引文献