Diurnal expression of clock genes in pineal gland and brain and plasma levels of melatonin and cortisol in Atlantic salmon parr and smolts.
Chronobiol Int
; 27(9-10): 1697-714, 2010 Oct.
Article
em En
| MEDLINE
| ID: mdl-20969518
ABSTRACT
In Atlantic salmon, the preadaptation to a marine life, i.e., parr-smolt transformation, and melatonin production in the pineal gland are regulated by the photoperiod. However, the clock genes have never been studied in the pineal gland of this species. The aim of the present study was to describe the diurnal expression of clock genes (Per1-like, Cry2, and Clock) in the pineal gland and brain of Atlantic salmon parr and smolts in freshwater, as well as plasma levels of melatonin and cortisol. By employing an out-of-season smolt production model, the parr-smolt transformation was induced by subjecting triplicate groups of parr to 6 wks (wks 0 to 6) under a 12 h12 h light-dark (LD) regime followed by 6 wks (wks 6 to 12) of continuous light (LL). The measured clock genes in both pineal gland and brain and the plasma levels of melatonin and cortisol showed significant daily variations in parr under LD in wk 6, whereas these rhythms were abolished in smolts under LL in wk 12. In parr, the pineal Per1-like and Cry2 expression peaked in the dark phase, whereas the pineal Clock expression was elevated during the light phase. Although this study presents novel findings on the clock gene system in the teleost pineal gland, the role of this system in the regulation of smoltification needs to be studied in more detail.
Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Glândula Pineal
/
Núcleo Supraquiasmático
/
Relógios Biológicos
/
Encéfalo
/
Salmo salar
/
Melatonina
Tipo de estudo:
Prognostic_studies
Limite:
Animals
Idioma:
En
Ano de publicação:
2010
Tipo de documento:
Article