title: Hemocyte-specific responses to the peroxidizing herbicide fomesafen in the pond snail Lymnaea stagnalis (Gastropoda, Pulmonata).
abstract: Responses of circulating hemocytes were studied in Lymnaea stagnalis exposed to 10, 30, 90, and 270 microg/L fomesafen for 24 and 504 h. Flow cytometry was used to quantify fomesafen-induced production of reactive oxygen species (ROS), phagocytic activity on Escherichia coli, and oxidative burst when hemocytes were challenged by E. coli or phorbol 12-myristate-13-acetate (PMA). Lysosomal membrane damage was assessed, using the neutral-red retention time (NRRT) assay. Exposure to fomesafen for 24 h resulted in increase in ROS levels and decreases in phagocytosis and the oxidative burst in PMA-stimulated hemocytes. After 504 h, intracellular levels of ROS returned to normal, but phagocytosis of E. coli was still inhibited and the associated oxidative burst significantly reduced. After both durations of exposure, decreases of NRRT indicated that lysosome membrane fragility increased with fomesafen concentration. Potential implications for the health and survival of the snails and consequences on populations are discussed.
authors.affiliation: UMR 6553 Ecobio CNRS Université de Rennes 1, Campus de Beaulieu, F-35042 Rennes cedex 35042, France.
authors.forename: Jacqueline
authors.initials: J
authors.lastname: Russo
authors.forename: Luz
authors.initials: L
authors.lastname: Lefeuvre-Orfila
authors.forename: Laurent
authors.initials: L
authors.lastname: Lagadic
mesh_terms: D000818:Animals; D001549:Benzamides / Q000633:toxicity*; D004305:Dose-Response Relationship, Drug; D004926:Escherichia coli / Q000276:immunology; D006434:Hemocytes / Q000187:drug effects* / Q000276:immunology; D006540:Herbicides / Q000633:toxicity*; D007425:Intracellular Membranes / Q000187:drug effects / Q000276:immunology; D008195:Lymnaea / Q000276:immunology* / Q000378:metabolism; D008247:Lysosomes / Q000187:drug effects / Q000276:immunology; D018384:Oxidative Stress / Q000187:drug effects; D010587:Phagocytosis / Q000187:drug effects; D017382:Reactive Oxygen Species / Q000378:metabolism; D013755:Tetradecanoylphorbol Acetate / Q000276:immunology; D013997:Time Factors
chemical_list: D001549:Benzamides; D006540:Herbicides; D017382:Reactive Oxygen Species; C088563:fomesafen; D013755:Tetradecanoylphorbol Acetate