Vasotocinergic and isotocinergic systems in the gilthead sea bream (Sparus aurata): An osmoregulatory story

To investigate the physiological roles of arginine vasotocin (AVT) and isotocin (IT) in osmoregulatory process in gilthead sea bream (Sparus aurata), a time course study (0, 12. h, and 1, 3, 7 and 14. days) has been performed in specimens submitted to hypoosmotic (from 40‰ salinity to 5‰ salinity) o...

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Bibliographic Details
Authors: Martos-Sitcha, Juan Antonio, Wunderink, Yvette S., Gozdowska, Magdalena, Kulczykowska, Ewa, Mancera, Juan Miguel, Martínez-Rodríguez, Gonzalo
Format: article
Status:Versión aceptada para publicación
Publication Date:2013
Country:España
Institution:Consejo Superior de Investigaciones Científicas (CSIC)
Repository:DIGITAL.CSIC. Repositorio Institucional del CSIC
OAI Identifier:oai:digital.csic.es:10261/103869
Online Access:http://hdl.handle.net/10261/103869
Access Level:Open access
Keyword:Stress
Teleost fish
Pro-vasotocin
Pro-isotocin
Osmoregulation
Description
Summary:To investigate the physiological roles of arginine vasotocin (AVT) and isotocin (IT) in osmoregulatory process in gilthead sea bream (Sparus aurata), a time course study (0, 12. h, and 1, 3, 7 and 14. days) has been performed in specimens submitted to hypoosmotic (from 40‰ salinity to 5‰ salinity) or hyperosmotic (from 40‰ salinity to 55‰ salinity) challenges. Plasma and liver osmoregulatory and metabolic parameters, as well as AVT and IT pituitary contents were determined concomitantly with hypothalamic pro-vasotocin (pro-VT) and pro-isotocin (pro-IT) mRNA expression levels. Previously, sequences coding for pro-VT and pro-IT cDNAs were cloned. Two osmoregulatory periods related to plasma osmolality and metabolic parameter variations could be distinguished: i) an adaptative period, from 12. h to 3. days after transfer, and ii) a chronic regulatory period, starting at day 3 after transfer. Higher values in hypothalamic pro-VT and pro-IT mRNA expression as well as in pituitary AVT and IT storage levels in both hypo- and/or hyper-osmotic transfers have been distinguished. These increase correlated with changes in plasma cortisol levels, suggesting an interaction between this hormone and pro-VT expression. Furthermore, pro-IT expression enhancement also suggests a role of the isotocinergic system as a modulator in the acute stress response induced by hyper-osmotic challenge in S. aurata. © 2013 Elsevier Inc.