Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
1993-8-13
pubmed:abstractText
The role of adenosine as a metabolic regulator of physiological processes in the brain was studied by measuring its concentrations and the activity of adenosine-metabolizing enzymes: 5'-nucleotidase, S-adenosylhomocysteine hydrolase, adenosine deaminase and adenosine kinase in the cerebral cortex of the rat. Other purine compounds, such as, inosine, hypoxanthine and adenine nucleotides were also studied. The purines' pattern was bimodal with high levels of adenosine, inosine and hypoxanthine during the light period reaching their peak at 12.00 h, 08.00 h and 16.00 h, respectively, and small increments during the night between 02.00 h and 04.00 h. The enzymatic activities showed, in general, an unimodal profile with low activity during the day and high activities at night. The adenine nucleotide profile showed a significant diminution between 12.00 h and 24.00 h. The high adenosine level during the day might be due to a diminution of adenine nucleotide and to the low activity of adenosine-metabolizing enzymes, suggesting an accumulation of the nucleoside. The night increase, although of less magnitude, is simultaneous to high activity of adenosine-metabolizing enzymes and could be due to an increased formation of the nucleoside. The present data and the findings from other authors strongly suggest that adenosine in the brain cortex of the rat can participate at least in two physiological processes: regulation of the sleep-wake cycle and replenishment of the adenine nucleotide pool.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0006-8993
pubmed:author
pubmed:issnType
Print
pubmed:day
28
pubmed:volume
612
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
115-21
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
1993
pubmed:articleTitle
Day-night variations of adenosine and its metabolizing enzymes in the brain cortex of the rat--possible physiological significance for the energetic homeostasis and the sleep-wake cycle.
pubmed:affiliation
Departamento de Bioenergética, UNAM, México, D.F.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't