Seale, A.P., Hawaii Institute of Marine Biology, University of Hawaii, Kaneohe, HI 96744, United States
Stagg, J.J., Hawaii Institute of Marine Biology, University of Hawaii, Kaneohe, HI 96744, United States, Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, Honolulu, HI 96822, United States
Yamaguchi, Y., Hawaii Institute of Marine Biology, University of Hawaii, Kaneohe, HI 96744, United States
Breves, J.P., Department of Biology and Center for Neuroendocrine Studies, University of Massachusetts, Amherst, MA 01003, United States
Soma, S., Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, University of Tokyo, Bunkyo, Tokyo 113-8657, Japan
Watanabe, S., Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, University of Tokyo, Bunkyo, Tokyo 113-8657, Japan
Kaneko, T., Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, University of Tokyo, Bunkyo, Tokyo 113-8657, Japan
Cnaani, A., Department of Poultry and Aquaculture, The Volcani Center, Agricultural Research Organization, Bet Dagan 50250, Israel
Harpaz, S., Department of Poultry and Aquaculture, The Volcani Center, Agricultural Research Organization, Bet Dagan 50250, Israel
Lerner, D.T., Hawaii Institute of Marine Biology, University of Hawaii, Kaneohe, HI 96744, United States, University of Hawaii Sea Grant College Program, University of Hawaii at Manoa, Honolulu, HI 96822, United States
Grau, E.G., Hawaii Institute of Marine Biology, University of Hawaii, Kaneohe, HI 96744, United States
Stagg, J.J., Hawaii Institute of Marine Biology, University of Hawaii, Kaneohe, HI 96744, United States, Department of Molecular Biosciences and Bioengineering, University of Hawaii at Manoa, Honolulu, HI 96822, United States
Yamaguchi, Y., Hawaii Institute of Marine Biology, University of Hawaii, Kaneohe, HI 96744, United States
Breves, J.P., Department of Biology and Center for Neuroendocrine Studies, University of Massachusetts, Amherst, MA 01003, United States
Soma, S., Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, University of Tokyo, Bunkyo, Tokyo 113-8657, Japan
Watanabe, S., Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, University of Tokyo, Bunkyo, Tokyo 113-8657, Japan
Kaneko, T., Department of Aquatic Bioscience, Graduate School of Agricultural and Life Sciences, University of Tokyo, Bunkyo, Tokyo 113-8657, Japan
Cnaani, A., Department of Poultry and Aquaculture, The Volcani Center, Agricultural Research Organization, Bet Dagan 50250, Israel
Harpaz, S., Department of Poultry and Aquaculture, The Volcani Center, Agricultural Research Organization, Bet Dagan 50250, Israel
Lerner, D.T., Hawaii Institute of Marine Biology, University of Hawaii, Kaneohe, HI 96744, United States, University of Hawaii Sea Grant College Program, University of Hawaii at Manoa, Honolulu, HI 96822, United States
Grau, E.G., Hawaii Institute of Marine Biology, University of Hawaii, Kaneohe, HI 96744, United States
Euryhaline teleosts are faced with significant challenges during changes in salinity. Osmoregulatory responses to salinity changes are mediated through the neuroendocrine system which directs osmoregulatory tissues to modulate ion transport. Prolactin (PRL) plays a major role in freshwater (FW) osmoregulation by promoting ion uptake in osmoregulatory tissues, including intestine. We measured mRNA expression of ion pumps, Na+/K+-ATPase α3-subunit (NKAα3) and vacuolar type H+-ATPase A-subunit (V-ATPase A-subunit); ion transporters/channels, Na+/K+/2Cl- co-transporter (NKCC2) and cystic fibrosis transmembrane conductance regulator (CFTR); and the two PRL receptors, PRLR1 and PRLR2 in eleven intestinal segments of Mozambique tilapia (Oreochromis mossambicus) acclimated to FW or seawater (SW). Gene expression levels of NKAα3, V-ATPase A-subunit, and NKCC2 were generally lower in middle segments of the intestine, whereas CFTR mRNA was most highly expressed in anterior intestine of FW-fish. In both FW- and SW-acclimated fish, PRLR1 was most highly expressed in the terminal segment of the intestine, whereas PRLR2 was generally most highly expressed in anterior intestinal segments. While NKCC2, NKAα3 and PRLR2 mRNA expression was higher in the intestinal segments of SW-acclimated fish, CFTR mRNA expression was higher in FW-fish; PRLR1 and V-ATPase A-subunit mRNA expression was similar between FW- and SW-acclimated fish. Next, we characterized the effects of hypophysectomy (Hx) and PRL replacement on the expression of intestinal transcripts. Hypophysectomy reduced both NKCC2 and CFTR expression in particular intestinal segments; however, only NKCC2 expression was restored by PRL replacement. Together, these findings describe how both acclimation salinity and PRL impact transcript levels of effectors of ion transport in tilapia intestine. © 2014 Elsevier Inc.
