Linked Life Data

11245922

Source:http://linkedlifedata.com/resource/pubmed/id/11245922

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2001-3-14
pubmed:abstractText
Aging leads to many changes in the expression of circadian rhythms, including reduced amplitude, altered relationship to the environmental illumination cycle, and reduced sensitivity to phase resetting signals. Neuropeptide synthesizing neurons in the suprachiasmatic nucleus (SCN), the principal circadian pacemaker in mammals, play a role in regulating pacemaker function and in coupling the pacemaker to overt circadian rhythms. Aging may alter the activity of neuropeptide neurons in the SCN, which could be reflected in changes in mRNA expression. Therefore, this study investigated whether aging alters the level or rhythm of expression of neuropeptide mRNAs in the SCN of male Syrian hamsters, a well established model for the study of age-related changes in circadian rhythms. Three age groups of hamsters (young [3--5 months old], middle-aged [12--15 months old] and old [19--22 months old] were sacrificed at five times of day. Their brains were dissected and sections through the suprachiasmatic nucleus were prepared and used for in situ hybridization for mRNAs for vasoactive intestinal peptide (VIP), arginine vasopressin (AVP) and somatostatin (SS). Aging selectively decreased the SCN expression of VIP mRNA without affecting AVP mRNA or SS mRNA. Also, only AVP mRNA expression exhibited a robust 24-h rhythm, in contrast to previous findings in other species that VIP mRNA and SS mRNA, as well as AVP mRNA, exhibit 24-h rhythms in the SCN. The present findings suggest that age-related reductions in VIP mRNA expression may contribute to the alterations in entrainment and attenuated sensitivity to phase resetting signals that are characteristic of aging. Furthermore, the results demonstrate that neuropeptide gene expression in the SCN is differentially regulated by aging and varies among species.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Mar
pubmed:issn
0169-328X
pubmed:author
pubmed:issnType
Print
pubmed:day
5
pubmed:volume
87
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
196-203
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Aging selectively suppresses vasoactive intestinal peptide messenger RNA expression in the suprachiasmatic nucleus of the Syrian hamster.
pubmed:affiliation
Department of Anatomy and Neurobiology, University of Kentucky Medical Center, 800 Rose Street, Lexington, KY 40536-0298, USA. mjdunc0@pop.edu.uky
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.