Linked Life Data

16098087

Source:http://linkedlifedata.com/resource/pubmed/id/16098087

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
2
pubmed:dateCreated
2005-8-15
pubmed:abstractText
In the mouse suprachiasmatic nucleus (SCN), melatonin activates MT1 and MT2 G-protein coupled receptors, which are involved primarily in inhibition of neuronal firing and phase shift of circadian rhythms. This study investigated the ability of melatonin to phase shift circadian rhythms in wild type (WT) and MT1 melatonin receptor knockout (KO) C57BL/6 mice. In WT mice, melatonin (90 microg/mouse, s.c.) administered at circadian time 10 (CT10; CT12 onset of activity) significantly phase advanced the onset of the circadian activity rhythm (0.60 +/- 0.09 hr, n = 41) when compared with vehicle treated controls (-0.02 +/- 0.07 hr, n = 28) (P < 0.001). In contrast, C57 MT1KO mice treated with melatonin did not phase shift circadian activity rhythms (-0.10 +/- 0.12 hr, n = 42) when compared with vehicle treated mice (-0.12 +/- 0.07 hr, n = 43). Similarly, in the C57 MT1KO mouse melatonin did not accelerate re-entrainment to a new dark onset after an abrupt advance of the dark cycle. In contrast, melatonin (3 and 10 pm) significantly phase advanced circadian rhythm of neuronal firing in SCN brain slices independent of genotype with an identical maximal shift at 10 pm (C57 WT: 3.61 +/- 0.38 hr, n = 3; C57 MT(1)KO: 3.45 +/- 0.11 hr, n = 4). Taken together, these results suggest that melatonin-mediated phase advances of circadian rhythms of neuronal firing in the SCN in vitro may involve activation of the MT2 receptor while in vivo activation of the MT1 and possibly the MT2 receptor may be necessary for the expression of melatonin-mediated phase shifts of overt circadian activity rhythms.
pubmed:grant
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0742-3098
pubmed:author
pubmed:issnType
Print
pubmed:volume
39
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
113-20
pubmed:dateRevised
2011-8-1
pubmed:meshHeading
pubmed:year
2005
pubmed:articleTitle
Effect of MT1 melatonin receptor deletion on melatonin-mediated phase shift of circadian rhythms in the C57BL/6 mouse.
pubmed:affiliation
Department of Molecular Pharmacology and Biological Chemistry, Northwestern University Feinberg School of Medicine, Chicago, IL 60611, USA. mdubo@northwestern.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S., Research Support, N.I.H., Extramural