Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
4
pubmed:dateCreated
1999-8-30
pubmed:abstractText
The purpose of the present study was to investigate the possible cellular location of 5-HT(1B) receptors on retinal and geniculate afferents in the rat suprachiasmatic nucleus (SCN). Biocular enucleation significantly decreased 5-HT(1B) binding site labeling (35%), specifically in the ventral part of the SCN, while monocular enucleation produced a decrease of smaller magnitude (12%), limited to the ventral part of the contralateral SCN, these results being consistent with the known distribution of retinal afferents in the nucleus. By contrast, bilateral geniculate lesion did not induce any significant variation of 5-HT(1B) binding site labeling in the SCN. Previously, we reported that serotonin (5-HT) synthesis inhibition by parachlorophenylalanine increases 5-HT(1B) binding site labeling in the SCN. Using saturation studies, we have now demonstrated that this upregulation reflected an increase in the total number of 5-HT(1B) binding sites (+41% in the dorsal and +67% in the ventral part of the SCN). Furthermore, we evaluated the effects of bilateral geniculate lesion after 5-HT stores depletion in order to overcome problems of technical resolution limits. The magnitude of upregulation was significantly decreased (27%) after bilateral geniculate lesion, suggesting that part of the 5-HT(1B) receptor population was located on geniculate axon terminals within the SCN. The possible involvement of 5-HT(1B) receptors, according to their cellular locations evidenced in the present study, in photic and nonphotic entrainment of the circadian clock is discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0887-4476
pubmed:author
pubmed:copyrightInfo
Copyright 1999 Wiley-Liss, Inc.
pubmed:issnType
Print
pubmed:day
15
pubmed:volume
33
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
314-23
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed-meshheading:10421712-Afferent Pathways, pubmed-meshheading:10421712-Animals, pubmed-meshheading:10421712-Axons, pubmed-meshheading:10421712-Dipeptides, pubmed-meshheading:10421712-Eye Enucleation, pubmed-meshheading:10421712-Fenclonine, pubmed-meshheading:10421712-Functional Laterality, pubmed-meshheading:10421712-Geniculate Bodies, pubmed-meshheading:10421712-Iodine Radioisotopes, pubmed-meshheading:10421712-Kinetics, pubmed-meshheading:10421712-Male, pubmed-meshheading:10421712-Rats, pubmed-meshheading:10421712-Rats, Sprague-Dawley, pubmed-meshheading:10421712-Receptor, Serotonin, 5-HT1B, pubmed-meshheading:10421712-Receptors, Serotonin, pubmed-meshheading:10421712-Regression Analysis, pubmed-meshheading:10421712-Retina, pubmed-meshheading:10421712-Serotonin, pubmed-meshheading:10421712-Serotonin Antagonists, pubmed-meshheading:10421712-Suprachiasmatic Nucleus, pubmed-meshheading:10421712-Visual Pathways
pubmed:year
1999
pubmed:articleTitle
Indirect evidence for an association of 5-HT(1B) binding sites with retinal and geniculate axon terminals in the rat suprachiasmatic nucleus.
pubmed:affiliation
Laboratoire des Interactions Fonctionnelles en Neuroendocrinologie, INSERM U501, Institut Fédératif Jean Roche, Faculté de Médecine Nord, Marseille, France.
pubmed:publicationType
Journal Article