Linked Life Data

21095192

Source:http://linkedlifedata.com/resource/pubmed/id/21095192

Statements in which the resource exists as a subject.
PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2011-1-17
pubmed:abstractText
Arginine vasotocin (AVT) and isotocin (IT) are two neurohypophysial peptide hormones for which a role in adaptation to environmental changes has been suggested in fish. In teleosts, there are only a few available studies about circadian changes of AVT and IT levels, and a role of those peptides in the circadian system has been mainly suggested on the basis of the role of the homologous hormone AVP in mammals. Herein, we evaluated the diurnal rhythms in plasma AVT, pituitary AVT and IT content and the hypothalamic pro-vasotocin (pro-VT) expression in rainbow trout kept under a natural photoperiod, as well as their persistence in constant darkness as a tool for defining circadian dependence. Trout kept under a natural light cycle showed clear diurnal rhythms in both circulating and pituitary AVT levels with peak values around the last hours of the light phase. Hypothalamic pro-VT mRNA was also rhythmically expressed with similar peak characteristics. These rhythms persisted in fish kept under constant darkness for nearly two consecutive days, although peaks were progressively attenuated and phase-advanced. An IT rhythm was also found in pituitary of the trout maintained under a natural photoperiod, but not in those kept under continuous darkness. These results suggest that rhythms of hypothalamic AVT synthesis might be regulated by endogenous circadian mechanisms, and these rhythms contribute to maintain a similar fluctuation in pituitary AVT secretion into the blood. A potential role for AVT in the circadian and seasonal time-keeping system of teleost fish, either as a component of the neural machinery that participates in the adaptation to cyclic environmental changes, or as a circadian/seasonal output signal, is also discussed.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Feb
pubmed:issn
1095-6840
pubmed:author
pubmed:copyrightInfo
Copyright © 2010 Elsevier Inc. All rights reserved.
pubmed:issnType
Electronic
pubmed:day
1
pubmed:volume
170
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
541-9
pubmed:meshHeading
pubmed:year
2011
pubmed:articleTitle
Diurnal rhythms in hypothalamic/pituitary AVT synthesis and secretion in rainbow trout: evidence for a circadian regulation.
pubmed:affiliation
Departamento de Biología Funcional y Ciencias de la Salud, Facultad de Biología, Universidad de Vigo, 36310 Vigo, Spain.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't