TY - JOUR
T1 - The mechanisms and costs of physiological and toxicological acclimation to waterborne silver in juvenile rainbow trout (Oncorhynchus mykiss)
AU - Galvez, F.
AU - Wood, C. M.
N1 - Funding Information:
Acknowledgements We thank Joe Gorsuch and Ken Robillard from Eastman Kodak Company (Rochester, N.Y., USA) and Trevor Smith from Kodak Canada Inc. for very helpful scientific liaison and comments on the manuscript. This work was funded by Kodak Canada Inc. and the Natural Sciences and Engineering Research Council of Canada (NSERC) through the Industrially Oriented Research program.
PY - 2002
Y1 - 2002
N2 - Juvenile rainbow trout were exposed to 0, 0.1, 1, 3, and 5 μg/l silver (Ag, as AgNO3) for 23 days. Specific growth rate, cumulative food consumption, food-conversion efficiency, and critical swimming speed (Ucrit) were significantly reduced during 5 μg/l Ag exposure, demonstrating a physiological cost of silver acclimation. Only the 5 μg/l Ag treatment had significant cumulative mortality (5.2%). Fish were most susceptible to silver on days 5 and 15. Exposure to 5 μg/l Ag significantly lowered plasma Na+ and Cl- on days 5 and 10, but plasma ion concentration recovered thereafter. Unidirectional Na+ uptake and gill Na/K-ATPase activity were significantly inhibited by 3 and 5 μg/l Ag exposure. Na+ uptake was inhibited by 3 μg/l Ag at day 5 alone, whereas the effects at the highest Ag exposure persisted until day 15. Gill Na/K-ATPase was inhibited on day 5 in both the 3 and 5 μg/l Ag treatments but increased to approx. 1.5 times of control levels by day 23. Only the 3 and 5 μg/l Ag treatments produced toxicological acclimation (at least twofold elevations in 168-h LC50 values in fish subsampled on days 15 and 23). We conclude that physiological acclimation results from compensatory changes in Na+ transport at the gills, and that these changes may eventually lead to toxicological acclimation.
AB - Juvenile rainbow trout were exposed to 0, 0.1, 1, 3, and 5 μg/l silver (Ag, as AgNO3) for 23 days. Specific growth rate, cumulative food consumption, food-conversion efficiency, and critical swimming speed (Ucrit) were significantly reduced during 5 μg/l Ag exposure, demonstrating a physiological cost of silver acclimation. Only the 5 μg/l Ag treatment had significant cumulative mortality (5.2%). Fish were most susceptible to silver on days 5 and 15. Exposure to 5 μg/l Ag significantly lowered plasma Na+ and Cl- on days 5 and 10, but plasma ion concentration recovered thereafter. Unidirectional Na+ uptake and gill Na/K-ATPase activity were significantly inhibited by 3 and 5 μg/l Ag exposure. Na+ uptake was inhibited by 3 μg/l Ag at day 5 alone, whereas the effects at the highest Ag exposure persisted until day 15. Gill Na/K-ATPase was inhibited on day 5 in both the 3 and 5 μg/l Ag treatments but increased to approx. 1.5 times of control levels by day 23. Only the 3 and 5 μg/l Ag treatments produced toxicological acclimation (at least twofold elevations in 168-h LC50 values in fish subsampled on days 15 and 23). We conclude that physiological acclimation results from compensatory changes in Na+ transport at the gills, and that these changes may eventually lead to toxicological acclimation.
KW - Metabolic costs
KW - Na/K-ATPase
KW - Rainbow trout
KW - Silver acclimation
KW - Unidirectional influx
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U2 - 10.1007/s00360-002-0287-7
DO - 10.1007/s00360-002-0287-7
M3 - Article
C2 - 12355227
AN - SCOPUS:0036931736
VL - 172
SP - 587
EP - 597
JO - Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology
JF - Journal of Comparative Physiology B: Biochemical, Systemic, and Environmental Physiology
SN - 0174-1578
IS - 7
ER -