Linked Life Data

12054193

Source:http://linkedlifedata.com/resource/pubmed/id/12054193

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2002-6-10
pubmed:abstractText
Several studies have demonstrated a variety of effects of intergeniculate leaflet (IGL) lesions on circadian rhythm regulation. Recent studies have suggested the possibility that certain rhythm functions attributed to the IGL are actually controlled by retinorecipient midbrain nuclei or other brain areas connected to the IGL. The present investigations evaluated whether midbrain lesions previously shown to block the phasic actions of benzodiazepine would also reduce or eliminate the period-lengthening effect of constant light (LL), a function that has been attributed to the IGL. Experiment 1 established that the circadian period of controls lengthened by about 0.57 h when the animals were transferred from constant dark (DD) to LL, but the magnitude of change was attenuated by about 50% in animals with IGL lesions caused by the neurotoxin N-methyl-D-aspartate (NMDA). In experiment 2, controls were compared to groups receiving either NMDA lesions of the pretectum or tectum or knife cuts designed to sever connections between the IGL and more medial retinorecipient nuclei. As in experiment 1, there were no differences between groups with respect to circadian period in DD. However, unlike experiment 1, all groups lengthened period equally in LL (overall mean increase = 0.57 h). Thus, the effect of LL on circadian period appears to be a joint result of photic information arriving at the circadian clock directly from the retinohypothalamic tract and indirectly through the IGL via the geniculohypothalamic tract, without involvement of visual midbrain. The results may have implications for the anatomical basis of Aschoff's rule.
pubmed:grant
pubmed:keyword
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Jun
pubmed:issn
0748-7304
pubmed:author
pubmed:issnType
Print
pubmed:volume
17
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
217-26
pubmed:dateRevised
2007-11-15
pubmed:meshHeading
pubmed:year
2002
pubmed:articleTitle
The intergeniculate leaflet, but not the visual midbrain, mediates hamster circadian rhythm response to constant light.
pubmed:affiliation
Department of Psychiatry, State University of New York at Stony Brook, NY 11794-8101, USA. lmorin@epo.som.sunysb.edu
pubmed:publicationType
Journal Article, Research Support, U.S. Gov't, P.H.S.