Linked Life Data

11255139

Source:http://linkedlifedata.com/resource/pubmed/id/11255139

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1
pubmed:dateCreated
2001-3-20
pubmed:abstractText
The contribution of amino acid oxidation to total energy expenditure is negligible during short-term intense exercise and accounts for 3-6% of the total adenosine triphosphate supplied during prolonged exercise in humans. While not quantitatively important in terms of energy supply, the intermediary metabolism of several amino acids-notably glutamate, alanine, and the branched-chain amino acids-affects other metabolites, including the intermediates within the tricarboxylic acid (TCA) cycle. Glutamate appears to be a key substrate for the rapid increase in muscle TCA cycle intermediates (TCAI) that occurs at the onset of moderate to intense exercise, due to a rightward shift of the reaction catalyzed by alanine aminotransferase (glutamate + pyruvate <==> alanine + 2-oxoglutarate). The pool of muscle TCAI declines during prolonged exercise, and this has been attributed to an increase in leucine oxidation that relies on one of the TCAI. However, this mechanism does not appear to be quantitatively important due of the relatively low maximal activity of branched-chain oxoacid dehydrogenase, the key enzyme involved. It has been suggested that an increase in TCAI is necessary to attain high rates of aerobic energy production and that a decline in TCAI may be a causative factor in local muscle fatigue. These topics remain controversial, but recent evidence suggests that changes in TCAI during exercise are unrelated to oxidative energy provision in skeletal muscle.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
1526-484X
pubmed:author
pubmed:issnType
Print
pubmed:volume
11
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
87-108
pubmed:dateRevised
2005-11-16
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Regulation of skeletal muscle amino acid metabolism during exercise.
pubmed:affiliation
Exercise Metabolism Research Group, Department of Kinesiology, McMaster University, Hamilton, Ontario L8S 4K1, Canada.
pubmed:publicationType
Journal Article, Review