Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
1987-6-12
pubmed:abstractText
Muscarinic receptor-stimulated phosphoinositide hydrolysis was investigated in rat brain during ontogeny by measuring the accumulation of [3H]inositol phosphates ([3H]InsPs) in cerebral cortex slices at various ages. Experiments with carbachol and acetylcholine showed that [3H]InsPs accumulation was maximal in 7-day-old rats (1477 +/- 98% of basal) and lowest in adult (75 days) rats (428 +/- 24% of basal). No differences were found in the EC50 values for both cholinergic agonists. This effect appeared to be mediated by the M1-muscarinic receptor subtype as it was blocked by pirenzepine with Ki = 29.1 +/- 7.1 nM (adults) and 87.9 +/- 18.2 nM (7-day-old rats). Incorporation of [3H]inositol into phospholipid decreased from day 3 to adulthood; however, when data of [3H]InsPs release were corrected for the incorporation at a given age, the highest stimulation by cholinergic agonists was still observed in 7-day-old rats. Among the other neurotransmitters tested (norepinephrine, histamine and serotonin), all known to stimulate phosphoinositide metabolism, none had the same developmental profile of [3H]InsPs accumulation as cholinergic agonists. In contrast to carbachol- and acetylcholine-stimulated phosphoinositide hydrolysis, the density of muscarinic binding sites, measured by [3H]quinuclidinyl benzilate binding, increased from day 3 to day 75. Acetylcholinesterase activity also increased during development. The dissociation of receptor binding sites from receptor-stimulated phosphoinositide metabolism suggests the presence of a more effective receptor-effector coupling at specific times of neonatal development, particularly 1 week. Furthermore, the fact that maximal stimulation of phosphoinositide hydrolysis coincides with the period of brain growth spurt in the rats suggests that this system in the cerebral cortex might be involved in the processes of cell division and differentiation.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
May
pubmed:issn
0022-3565
pubmed:author
pubmed:issnType
Print
pubmed:volume
241
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
421-7
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
1987
pubmed:articleTitle
Developmental changes in muscarinic receptor-stimulated phosphoinositide metabolism in rat brain.
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, U.S. Gov't, Non-P.H.S.