title: Influence of temperature, pH, oxygenation, water-type and substrate on biomarker responses in the freshwater clam Corbicula fluminea (Müller).
abstract: We investigated the influence of abiotic factors on responses of components of detoxification metabolism of phases I and II, indicators related to oxidative stress and propionylcholinesterase, proposed as biomarkers of pollution in Corbicula fluminea. Combined effects of temperature (10 and 20 degrees C), water-type (water purified by reverse-osmosis, lake water from the collection site and tap water) and habitat substrate (presence and absence of sand) were assessed in a five-day experiment. Additionally, clams were exposed to hypoxia or submitted to acidic, neutral or alkaline conditions at 20 degrees C, in lake water, without sand, for five days. Responses of biomarkers were generally higher when clams were placed in tap water, except for level of peroxidised lipids (PL). Catalase (CAT) and NADH-cytochrome c reductase (NADH-red.) activities increased whereas propionylcholinesterase (PChE) activity decreased in absence of sand. Decreasing temperature resulted in depressing PChE and NADPH-cytochrome c reductase (NADPH-red.) activities. Hypoxia induced an increase of CAT activity and glutathione S-transferase activity towards ethacrynic acid and a decrease of PL level. CAT and NADH-red. activities as well as PL level were reduced when clams were exposed to acidic and/or alkaline conditions. These results indicate that effects of abiotic factors should be taken into account in environmental studies.
authors.affiliation: Laboratoire de Physico-Toxicochimie des Systèmes Naturels (LPTC), UPRES-A 5472 CNRS, Département de Toxicologie Biochimique, Université Bordeaux 1, Avenue des Facultés, Talence, France. mlvidal@viola.fr
authors.forename: Mary-Laure
authors.initials: ML
authors.lastname: Vidal
authors.forename: Anne
authors.initials: A
authors.lastname: Bassères
authors.forename: Jean-François
authors.initials: JF
authors.lastname: Narbonne
mesh_terms: D000704:Analysis of Variance; D000818:Animals; D015415:Biomarkers / Q000032:analysis*; D049872:Bivalvia / Q000187:drug effects / Q000201:enzymology* / Q000378:metabolism*; D002374:Catalase / Q000378:metabolism; D002802:Cholinesterases / Q000378:metabolism; D005602:France; D005618:Fresh Water / Q000737:chemistry*; D005982:Glutathione Transferase / Q000378:metabolism; D006863:Hydrogen-Ion Concentration; D008054:Lipid Peroxides / Q000378:metabolism; D009245:NADH Dehydrogenase / Q000378:metabolism; D010100:Oxygen / Q000378:metabolism* / Q000494:pharmacology; D013379:Substrate Specificity; D013696:Temperature; D014873:Water Pollutants / Q000494:pharmacology
chemical_list: D015415:Biomarkers; D008054:Lipid Peroxides; D014873:Water Pollutants; D002374:Catalase; D009245:NADH Dehydrogenase; D005982:Glutathione Transferase; C025181:propionylcholinesterase; D002802:Cholinesterases; D010100:Oxygen