Effects of Recombinant Aquaporin 3 and Seawater Acclimation on the Expression of Aquaporin 3 and 8 mRNAs in the Parr and Smolt Stages of Rainbow Trout, Oncorhynchus mykiss

  • Kim, Na Na (Marine Ecosystem and Biological Research Center, KIOST) ;
  • Choi, Young Jae (Division of Marine BioScience, College of Ocean Science and Technology Korea Maritime and Ocean University) ;
  • Lim, Sang-Gu (Jeju Fisheries Research Institute, National Institute of Fisheries Science) ;
  • Kim, Bong-Seok (Jeju Fisheries Research Institute, National Institute of Fisheries Science) ;
  • Choi, Cheol Young (Division of Marine BioScience, College of Ocean Science and Technology Korea Maritime and Ocean University)
  • Received : 2016.02.22
  • Accepted : 2016.03.17
  • Published : 2016.06.30


This study aimed to examine the role of two aquaporin isoforms (AQP3 and AQP8) in response to the hyperosmotic challenge of transitioning from freshwater (FW) to seawater (SW) during parr and smoltification (smolt) using the rainbow trout, Oncorhynchus mykiss. We examined the changes in the expression of AQPs mRNAs in the gills and intestine of the parr and smolt stages of rainbow trout transferred from FW to SW using quantitative real-time PCR in an osmotically changing environment [FW, SW, and recombinant AQP3 (rAQP3) injection at two dosage rates]. Correspondingly, AQPs were greater during smoltification than during parr stages in the rainbow trout. Plasma osmolality and gill $Na^+/K^+$-ATPase activity increased when the fish were exposed to SW, but these parameters decreased when the fish were exposed to SW following treatment with rAQP3 during the transition to seawater. Our results suggest that AQPs play an important role in water absorbing mechanisms associated with multiple AQP isoforms in a hyperosmotic environment.


Supported by : Korea Institute of Ocean Science and Technology, National Institute of Fisheries Science


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