Linked Life Data

10677628

Source:http://linkedlifedata.com/resource/pubmed/id/10677628

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
1-2
pubmed:dateCreated
2000-5-10
pubmed:abstractText
Middle age is associated with changes in circadian rhythms (e.g., alterations in the timing of the circadian wheel running rhythm) which resemble changes induced by selective destruction of the serotonergic input to the suprachiasmatic nucleus (SCN), the principal mammalian circadian pacemaker. We hypothesized that serotonergic neurotransmission in the SCN is decreased in middle-aged hamsters, as compared to young adults. This hypothesis was tested indirectly by investigating the effect of aging on two markers of serotonin neurotransmission, 5-HT(1B) receptors and serotonin reuptake sites, which are regulated by serotonin. Previous studies have shown that experimentally induced decreases in serotonergic neurotransmission increase 5-HT(1B) receptors but decrease serotonin reuptake sites. Quantitative autoradiography was conducted using [125I]iodocyanopindolol ([125I]ICYP) and [3H]paroxetine, selective radioligands for the 5-HT(1B) receptors and the serotonin reuptake sites, respectively. Consistent with the hypothesis, specific ([125I]ICYP binding was significantly elevated in the SCN of middle-aged hamsters, as compared to young hamsters. The results also showed that serotonin reuptake sites in the SCN were significantly increased in both middle-aged and old hamsters, as compared to young controls. This result could not have been caused by decreased serotonin release. Alternatively, increased serotonin reuptake, which would reduce serotonin levels in the synaptic cleft, may cause or contribute to the increase in 5-HT(1B) receptor binding in the SCN in middle aged animals. These results show that the SCN exhibits changes in serotonergic function during middle age, which has been characterized by changes in the expression of circadian rhythms. Because these changes occur during middle age, they probably reflect the aging process, rather than senescence or disease.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
0006-8993
pubmed:author
pubmed:issnType
Print
pubmed:day
21
pubmed:volume
856
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
213-9
pubmed:dateRevised
2007-11-14
pubmed:meshHeading
pubmed:year
2000
pubmed:articleTitle
Aging regulates 5-HT(1B) receptors and serotonin reuptake sites in the SCN.
pubmed:affiliation
Department of Anatomy, University of Kentucky Medical Center, 800 Rose Street, Lexington, KY, USA. mjdunc0@pop.edu.uky
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.