The use of biomarkers in Daphnia magna toxicity testing: 5. In vivo alterations in the carbohydrate metabolism of Daphnia magna exposed to sublethal concentrations of mercury and lindane
De Coen, W.M.; Janssen, C.R.; Segner, H. (2001). The use of biomarkers in Daphnia magna toxicity testing: 5. In vivo alterations in the carbohydrate metabolism of Daphnia magna exposed to sublethal concentrations of mercury and lindane. Ecotoxicol. Environ. Saf. 48(3): 223-234 In: Ecotoxicology and Environmental Safety. Academic Press/Elsevier: Amsterdam, Netherlands etc. ISSN 0147-6513; e-ISSN 1090-2414, more | |
Keywords | Aquatic organisms > Freshwater organisms > Fish > Freshwater fish Biomarkers Cell constituents > Cell organelles > Mitochondria Chemical compounds > Organic compounds > Organometallic compounds > Methyl mercury Chemical reactions > Lysis > Carbohydrate metabolism > Decomposition > Glycolysis Crabs Crabs Endrin Enzymes > Transferases > Glycosyltransferases > Hexosyltransferases > Phosphorylase > Glycogen phosphorylase Glycolysis Invertebrates > Arthropods > Crustacea > Malacostraca > Decapoda > Shellfish > Crabs Lactate dehydrogenase Metabolism > Energy metabolism Peptides > Proteins > Enzymes > Oxidoreductases > Alcohol oxidoreductases > Lactate dehydrogenase Pesticides > Avicides > Cyclodiene insecticides > Endrin Pollutants Population dynamics Toxicology Daphnia magna Straus, 1820 [WoRMS]
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Authors | | Top | - De Coen, W.M., more
- Janssen, C.R., more
- Segner, H.
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Abstract | Aspects of the carbohydrate metabolism of Daphnia magna exposed for 48 and 96 h to sublethal concentrations of mercury and lindane were investigated. General as well as toxicant-specific perturbations in the intermediary metabolism mere observed. Both model toxicants caused an increase in glycolytic and hexose-monophosphate shunt activity. Mercury exposure increased lactate dehydrogenase and isocitrate activity (only after 96 h), while lindane exposure, on the contrary, inhibited the cellular lactate formation and increased the Krebs' cycle activity (only after 48 h), Daphnids exposed to sublethal mercury concentrations clearly exhibited increased glycogenolytic activity, while in lindane-exposed organisms mainly glycogen phosphorylase inhibition was detected, The short-term enzyme-based effect levels (48-96 h LOEC and EC10 values) were compared with the effects on the population dynamics. This evaluation for both model toxicants suggests that threshold levels (LOEC or EC10 values) based on pyruvate kinase activity after 48 and 96 h of exposure could be potential early warning signals for long-term effects. A set of enzymatic endpoints, based on the intermediary metabolism, is suggested to characterize the metabolic state of the daphnids. |
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