Effects of warm acclimation on Na+,K+-ATPase α-subunit expression in chloride cells of Antarctic fish
Version of Record online: 23 MAY 2005
Copyright © 2005 Wiley-Liss, Inc.
The Anatomical Record Part A: Discoveries in Molecular, Cellular, and Evolutionary Biology
Volume 285A, Issue 1, pages 600–609, July 2005
How to Cite
Brauer, P. R., Sanmann, J. N. and Petzel, D. H. (2005), Effects of warm acclimation on Na+,K+-ATPase α-subunit expression in chloride cells of Antarctic fish. Anat. Rec., 285A: 600–609. doi: 10.1002/ar.a.20203
- Issue online: 21 JUN 2005
- Version of Record online: 23 MAY 2005
- Manuscript Accepted: 9 MAR 2005
- Manuscript Received: 14 JAN 2005
- National Science Foundation-Office of Polar Programs. Grant Number: OPP0229462
- chloride cell;
The teleosts Trematomus bernacchii thrive in southern oceanic waters with temperatures below 0°C. These fish have serum osmolalities almost double those found in fish of temperate waters, thereby lowering their serum's freezing point and the energy needed for ionic homeostasis. Upon warm acclimation to 4°C, T. bernacchii decrease their serum osmolality and increase the Na+,K+-ATPase activity in their gills. Na+,K+-ATPase α1-, α2-, and α3-subunit isoforms are expressed in the gills of T. bernacchii and it is thought that Na+,K+-ATPase subunit composition in chloride cells changes with warm acclimation. Using immunohistochemistry, we compared the number of chloride cells expressing various α-isoforms of the Na+,K+-ATPase in the gills of cold- and warm-acclimated T. bernacchii. We found no change in the number of α2- or α3-immunopositive cells in warm-acclimated fish gills or in the number of cells immunopositive for the Na+,K+,2Cl− cotransporter. However, the number of pan-α-immunopositive (recognizing all three α-isoforms) and α1-immunopositive cells both increased in warm-acclimated fish. This suggests that changes in the number of α1-isoform-expressing chloride cells could contribute to the increased Na+,K+-ATPase activity that occurs with warm-acclimation. © 2005 Wiley-Liss, Inc.