|
|
||||||||
Department of Animal Science, University of British Columbia, Vancouver, British Columbia, Canada V6T 1Z4
Few studies have made direct estimates of the energy required for ion transport in gills of freshwater (FW) and seawater (SW) fish. Oxygen consumption was measured in excised gill tissue of FW-adapted cutthroat trout (Oncorhynchus clarki clarki) to estimate the energy cost of NaCl transport in that osmoregulatory organ. Ouabain (0.5 mM) and bafilomycin A1 (1 µM) were used to inhibit the Na+-K+ and H+ pumps, respectively. Both inhibitors significantly decreased gill tissue oxygen consumption, accounting for 37% of total tissue respiration. On a whole mass basis, the cost of NaCl uptake in the FW trout gill was estimated to be 1.8% of whole animal oxygen uptake. An isolated, saline-perfused gill arch preparation was also used to compare gill energetics in FW- and SW-adapted trout. The oxygen consumption of FW gills was significantly (33%) higher than SW gills. On a whole animal basis, total gill oxygen consumption in FW and SW trout accounted for 3.9 and 2.4% of resting metabolic rate, respectively. The results of both experiments suggest that the energy cost of NaCl transport in FW and SW trout gills represents a relatively small (<4%) portion of the animal's total energy budget.
oxygen consumption; bafilomycin; proton pump; ouabain; sodium pump; Oncorhynchus clarki clarki
This article has been cited by other articles:
![]() |
K. Deigweiher, N. Koschnick, H.-O. Portner, and M. Lucassen Acclimation of ion regulatory capacities in gills of marine fish under environmental hypercapnia Am J Physiol Regulatory Integrative Comp Physiol, November 1, 2008; 295(5): R1660 - R1670. [Abstract] [Full Text] [PDF] |
||||
![]() |
P. Boily, B. B. Rees, and L. A. C. Williamson Vertebrate osmoregulation: a student laboratory exercise using teleost fish Advan Physiol Educ, December 1, 2007; 31(4): 352 - 357. [Abstract] [Full Text] [PDF] |
||||
![]() |
C. M. Wood, M. Kajimura, K. A. Sloman, G. R. Scott, P. J. Walsh, V. M. F. Almeida-Val, and A. L. Val Rapid regulation of Na+ fluxes and ammonia excretion in response to acute environmental hypoxia in the Amazonian oscar, Astronotus ocellatus Am J Physiol Regulatory Integrative Comp Physiol, May 1, 2007; 292(5): R2048 - R2058. [Abstract] [Full Text] [PDF] |
||||
![]() |
D. H. Evans, P. M. Piermarini, and K. P. Choe The Multifunctional Fish Gill: Dominant Site of Gas Exchange, Osmoregulation, Acid-Base Regulation, and Excretion of Nitrogenous Waste Physiol Rev, January 1, 2005; 85(1): 97 - 177. [Abstract] [Full Text] [PDF] |
||||
![]() |
A. Shingles, D. J. McKenzie, E. W. Taylor, A. Moretti, P. J. Butler, and S. Ceradini Effects of sublethal ammonia exposure on swimming performance in rainbow trout (Oncorhynchus mykiss) J. Exp. Biol., January 8, 2001; 204(15): 2691 - 2698. [Abstract] [Full Text] [PDF] |
||||
| HOME | HELP | FEEDBACK | SUBSCRIPTIONS | ARCHIVE | SEARCH | TABLE OF CONTENTS |
| Visit Other APS Journals Online |