How does oxidative stress relate to thermal tolerance in the Antarctic bivalve Yoldia eightsi ?


Contact
dabele [ at ] awi-bremerhaven.de

Abstract

Short and long-term exposure to elevated temperatures were studied in the Antarctic stenothermal protobranch bivalve Yoldia eightsi from Potter Cove, King George Island (South Shetlands, Antarctica). Above a breakpoint temperature of 2°C - the upper habitat temperature for the Potter Cove Yoldia eightsi stock - both routine and standard metabolic rate (SMR) increased steeply. The fraction of metabolism allocated to SMR, as well as the number of intervals of elevated activity per hour increased significantly with temperature. During acute exposure, ATP concentrations in the foot muscle peaked at 2°C and fell at 5°C, whereas superoxide dismutase activity decreased upon warming.Slow stepwise warming to a final temperature of 11°C resulted in a significant decrease of SOD activity. Malondialdehyde concentration increased compared with controls at 0°C. In contrast to the effect of short term exposure, tissue adenylate concentrations displayed a mild increase towards higher temperatures during slow warming, indicating an acclimation response. A switch to anaerobic energy production could not be observed up to 11°C, demonstrating a higher level of thermal tolerance than in other Antarctic ectotherms, or a failure of the relevant pathways in Yoldia eightsi. The imbalance between pro- and antioxidant processes upon warming indicate oxidative stress to be one feature accompanying early heat stress in Yoldia eightsi.



Item Type
Article
Authors
Divisions
Programs
Publication Status
Published
Eprint ID
4075
Cite as
Abele, D. , Tesch, C. , Wencke, P. and Pörtner, H. O. (2001): How does oxidative stress relate to thermal tolerance in the Antarctic bivalve Yoldia eightsi ? , Antarctic Science 13, pp. 111-118 .


Download
[thumbnail of Fulltext]
Preview
PDF (Fulltext)
Abe2001a.pdf

Download (830kB) | Preview
Cite this document as:

Share
Add to AnyAdd to TwitterAdd to FacebookAdd to LinkedinAdd to PinterestAdd to Email

Research Platforms

Campaigns
N/A


Actions
Edit Item Edit Item