Differential effects of temperature and maturity stage on hepatic estrogen receptor characteristics of Atlantic salmon

• Published in: Comparative Biochemistry and Physiology Part A: Molecular & Integrative Physiology
• Main Authors: Watts, M, Pankhurst, NW, King, H, Geraghty, DP
• Format: Article in Journal/Newspaper
• Language: English
• Published: Elselvier Inc. 2005
• Subjects: Agricultural and Veterinary Sciences; Fisheries Sciences; Aquaculture; Austral; Atlantic salmon; Salmo salar
• Online Access: https://doi.org/10.1016/j.cbpb.2005.02.002; http://www.ncbi.nlm.nih.gov/pubmed/15792603; http://ecite.utas.edu.au/32835

In order to determine if elevated temperature during vitellogenesis had a detrimental effect on hepatic estrogen receptors of Atlantic salmon (Salmo salar), 3H-estradiol saturation binding analysis, using one- and two-site binding models, was carried out on extracts of hepatic cytosols from fish held at 14, 18 or 22C over the austral period of peak vitellogenesis (February to April). With one-site binding analysis, no temperature related difference in either receptor affinity (Kd) or number (B max) was found at each sampling point, but there was an apparent decrease in both affinity and number at each temperature over the period of the study. However, some analyses, notably at 22C during February, were best described using a two-site binding model. At this temperature and time, there was a clear separation of binding affinity into high and low components (K d=0.67S.E. 0.05 and 20S.E. 5.6 nM, respectively) (n=4), which suggests that February was a critical time of temperature related hepatic sensitivity to estrogen. These results support those of other studies where we found that February was also a sensitive time with respect to temperature impairment of in vitro follicular estrogen synthesis, and the greatest period of in vivo temperature sensitivity. 2005 Elsevier Inc. All rights reserved.