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Temperature and salinity are important abiotic factors for aquatic invertebrates. We investigated the influence of different salinity regimes on thermotolerance, energy metabolism and cellular stress defense mechanisms in amphipods Gammarus lacustris Sars from two populations. We exposed amphipods to different thermal scenarios and determined their survival as well as activity of major antioxidant enzymes (peroxidase, catalase, glutathione S-transferase) and parameters of energy metabolism (content of glucose, glycogen, ATP, ADP, AMP and lactate). Amphipods from a freshwater population were more sensitive to the thermal challenge, showing higher mortality during acute and gradual temperature change compared to their counterparts from a saline lake. A more thermotolerant population from a saline lake had high activity of antioxidant enzymes. The energy limitations of the freshwater population (indicated by low baseline glucose levels, downward shift of the critical temperature of aerobic metabolism and inability to maintain steady-state ATP levels during warming) was observed, possibly reflecting a trade-off between the energy demands for osmoregulation under the hypo-osmotic condition of a freshwater environment and protection against temperature stress.
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A Comparative Study of Antioxidant Enzymes Activity to Heat Shock in Amphipods Gmelinoides fasciatus of Littoral Community of Lake Baikal and Thermal Springs
The aim of the current study was to comparative assessment of the antioxidant enzymes activity (peroxidase, catalase, glutathione S-transferase) in endemic species Gmelinoides fasciatus (Stebbing, 1899) inhabitants of the littoral community of the Lake Baikal and the thermal spring under short term thermal stress. It was shown, that the exposure of G. fasciatus from different areas to acute temperature stress didn’t lead to changes in the activities of three key enzymes of the antioxidant system. However, it was found that the activity of glutathione S-transferase in the control animals of thermal springs population is higher than in animals of Lake Baikal. This can be determined by peculiarities of environment of different populations.
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- Award ID(s):
- 9531011
- PAR ID:
- 10026319
- Date Published:
- Journal Name:
- Journal of stress physiology & biochemistry
- Volume:
- 12
- Issue:
- 4
- ISSN:
- 1997-0838
- Page Range / eLocation ID:
- 31-37
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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