Linked Life Data

14679505

Source:http://linkedlifedata.com/resource/pubmed/id/14679505

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
6-7
pubmed:dateCreated
2003-12-17
pubmed:abstractText
The involvement of brain lactate in neuronal metabolism was analyzed by ex vivo NMR spectroscopy with rats under the effects of pentobarbital, alphachloralose or morphine, which were infused with a solution of either [1-(13)C]glucose+lactate or glucose+[3-(13)C]lactate for 20 min. Electroencephalogram recordings indicated different brain electrical activity levels under the three drugs with a clear distinction between pentobarbital, on the one hand, and alphachloralose and morphine on the other. Labeling of metabolites in brain perchloric acid extracts and of blood glucose and lactate was determined by (13)C- and/or (1)H-observed/(13)C-edited-NMR spectroscopy. The following were found: (i) the ratio between glutamate C3 and C4 (13)C-enrichments increased from pentobarbital to alphachloralose and morphine whatever the labeled precursor, indicating a link between metabolic and electrical activity; (ii) under glucose+[3-(13)C]lactate infusion, alanine C3 and acetyl-CoA C2 enrichments were higher than that of lactate C3, revealing the occurrence of an isotopic dilution of the brain exogenous lactate (arising from blood) by lactate from brain (endogenous lactate); the latter was synthesized from glycolysis in a compartment other than the neurons; (iii) the contributions of labeled glucose and lactate to acetyl-CoA C2 enrichment indicated that the involvement of blood glucose relative to that of blood lactate to brain metabolism was correlated with brain activity. It can therefore be concluded that the brain electrical activity-dependent increase in the contribution of blood glucose relative to that of blood lactate to brain metabolism occurred partly via the increase in the metabolism of lactate generated from astrocytic glycolysis. This conclusion supports the hypothesis of an astrocyte-neuron lactate shuttle component in the coupling mechanism between cerebral activity and energy metabolism.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0952-3480
pubmed:author
pubmed:copyrightInfo
Copyright 2003 John Wiley & Sons, Ltd.
pubmed:issnType
Print
pubmed:volume
16
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
430-9
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:articleTitle
Involvement of brain lactate in neuronal metabolism.
pubmed:affiliation
Unité de Résonance Magnétique des Systèmes Biologiques, UMR 5536, CNRS-Université Victor Segalen, case 93, 146 rue Léo-Saignat, 33076 Bordeaux, France.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't