Lushchak, V.I., Bagnyukova, T.V., Lushchak, O.V.,
Storey, J.M. and Storey, K.B. 2005. Hypoxia and recovery
perturb free radical processes and antioxidant potential in common carp (Cyprinus
carpio) tissues. Int. J. Biochem. Cell Biol. 37: 1319-1330.
Volodymyr I. Lushchak, Tetyana V. Bagnyukova,
Oleh V. Lushchak, Janet M. Storey, Kenneth B. Storey
Abstract
The effects of hypoxia
exposure and subsequent normoxic recovery on the levels of lipid peroxides
(LOOH), thiobarbituric acid reactive substances (TBARS), carbonylproteins,
total glutathione levels, and the activities of six antioxidant enzymes were
measured in brain, liver, kidney and skeletal muscle of the common carp Cyprinus carpio. Hypoxia exposure (0.25% of normal
oxygen level) for 5 hours generally decreased the levels of oxidative damage
products, but in liver TBARS content were elevated. Hypoxia stimulated
increases in the activities of catalase (by 1.7-fold) and glutathione
peroxidase (GPx) (by 1.3-fold) in brain supporting
the idea that anticipatory preparation takes place in order to deal with the
oxidative stress that will occur during reoxygenation. In liver, only GPx activity was reduced under hypoxia and reoxygenation
while other enzymes were unaffected. Kidney showed decreased activity of GPx under aerobic recovery but SOD and catalase responded
with sharp increases in activities. Skeletal muscle showed minor changes with a
reduction in GPx activity under hypoxia exposure and
an increase in SOD activity under recovery. Responses by antioxidant defenses
in carp organs appear to include preparatory increases during hypoxia by some
antioxidant enzymes in brain but a more direct response to oxidative insult
during recovery appears to trigger enzyme responses in kidney and skeletal
muscle.