Advisor(s)
Abstract(s)
Prolactin (PRL), growth hormone (GH) and somatolactin (SL) expression was studied in gilthead sea
bream (Sparus auratus) in response to several different stressors (salinity, food deprivation or stocking
density). In the first experiment, specimens were acclimated during 100 days at three different environmental
salinities: low salinity water (LSW, 6 ppt), brackish water (BW, 12 ppt) and seawater (SW, 38 ppt).
Osmoregulatory parameters corresponded to those previously reported for this species under similar
osmotic conditions. Pituitary PRL expression increased with decreasing environmental salinity, and
was significantly different between SW- and LSW-acclimated fish. Pituitary GH expression was similar
between SW- and BW-acclimated fish but decreased in LSW-acclimated specimens. Pituitary SL expression
had a ‘‘U-shaped” relationship to environmental salinity with the lowest expression in BW-acclimated
fish. In a second experiment SW-acclimated specimens were randomly assigned to one of four
treatments and maintained for 14 days: (1) fed fish under low density (LD, 4 kg m!3); (2) fed fish under
high density (HD, 70 kg m!3); (3) food deprived fish under LD; and (4) food deprived fish under HD.
Plasma glucose and cortisol levels corresponded to those previously reported in S. auratus under similar
experimental conditions. Pituitary PRL and SL expression increased in fish maintained under HD and
decreased in food deprived fish. In conclusion, an effect of environmental salinity on pituitary PRL and
GH expression has been demonstrated. In addition, crowding stress seems to interact with food deprivation
in S. auratus and this is reflected by changes in pituitary PRL, GH and SL expression levels.
Description
Keywords
Food deprivation GH Osmoregulation PRL SL Sea bream Sparus auratus Stocking density
Citation
Raúl Laiz-Carrión, Juan Fuentes, Begoña Redruello, José M. Guzmán, María P. Martín del Río, Deborah Power, Juan M. Mancera, "Expression of pituitary prolactin, growth hormone and somatolactin is modified in response to different stressors (salinity, crowding and food-deprivation) in gilthead sea bream Sparus auratus" in General and Comparative Endocrinology 162 (2009) 293–300.
Publisher
Elsevier