Linked Life Data

9778576

Source:http://linkedlifedata.com/resource/pubmed/id/9778576

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4-5
pubmed:dateCreated
1998-12-29
pubmed:abstractText
Pyruvate recycling is a well established pathway in the liver, but in the brain, the cellular localization of pyruvate recycling remains controversial and its physiological significance is unknown. In cultured cortical astrocytes, pyruvate formed from [U-13C]glutamate was shown to re-enter the TCA cycle after conversion to acetyl-CoA, as demonstrated by the labelling patterns in aspartate C-2 and C-3, lactate C-2, and glutamate C-4, which provides evidence for pyruvate recycling in astrocytes. This finding is in agreement with previous studies of astrocytic cultures, in which pyruvate recycling has been described from [U-13C]glutamine, in the presence of glutamate, and from [U-13C]aspartate. Pyruvate recycling in brain was studied in fasted rats receiving either an intraperitoneal or a subcutaneous injection of [1,2-13C]acetate followed by decapitation 30 min later. Extracts of cortical tissue were analysed with 13C-NMR spectroscopy and total amounts of amino acids quantified by HPLC. Plasma extracts were analysed with 1H- and 13C-NMR spectroscopy, and showed a significantly larger amount of [1, 2-13C]acetate in the intraperitoneal group compared to the subcutaneous group. Furthermore, a small amount of label was detected in glucose in both groups. In the subcutaneously injected rats, [4-13C]glutamate and [2-13C]GABA were less enriched than plasma glucose, which might have been the precursor. In the intraperitoneally injected rats, however, pyruvate formation from [1, 2-13C]acetate, and re-entry of this pyruvate into the TCA cycle was demonstrated by the presence of greater 13C enrichment in [4-13C]glutamate and [4-13C]glutamine compared to the subcutaneous group, probably resulting from the significantly higher [1, 2-13C]acetate concentration in brain and plasma.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:issn
0378-5866
pubmed:author
pubmed:issnType
Print
pubmed:volume
20
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
389-98
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1998
pubmed:articleTitle
In vitro and ex vivo 13C-NMR spectroscopy studies of pyruvate recycling in brain.
pubmed:affiliation
Department of Pharmacology and Toxicology, Medical Faculty, Norwegian University of Science and Technology, Trondheim, Norway.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't