title: Acetylcholinesterase inhibition in the crayfish Procambarus clarkii exposed to fenitrothion.
abstract: Laboratory and field studies were conducted to evaluate the effects of fenitrothion (O,O-dimethyl O-4-nitro-m-tolyl phosphorothioate) on the crayfish Procambarus clarkii. Acetyl- and butyryl-cholinesterase activities were measured in the muscle of P. clarkii exposed to different doses of fenitrothion (4, 20, and 100 microg/liter) for different times (up to 48 hr). A positive correlation was found between both cholinesterases, and acetylcholinesterase (AChE) was selected as a biomarker of exposure to this compound. Significant AChE depression (20%) was detected 2 hr after exposure to 20 microg/liter of fenitrothion, reaching a maximum at 48 hr (47%), followed by a slow recovery. Reactivation techniques using the nucleophilic reagent pyridine 2-aldoxime methiodide were assayed in fenitrothion-poisoned specimens, and the results suggested the utility of this method to diagnose exposure, particularly when control animals are not available. Finally, AChE inhibition was used to test a field population of P. clarkii potentially exposed to high concentrations of the organophosphorus pesticide fenitrothion, and a 55% inhibition was detected.
authors.affiliation: Environmental Chemistry Department, CID, CSIC, Jordi Girona, 18, Barcelona, 08034, Spain.
authors.forename: E
authors.initials: E
authors.lastname: Escartín
authors.forename: C
authors.initials: C
authors.lastname: Porte
mesh_terms: D000110:Acetylcholinesterase / Q000097:blood*; D000818:Animals; D003400:Astacoidea / Q000378:metabolism; D002800:Cholinesterase Inhibitors / Q000633:toxicity*; D002801:Cholinesterase Reactivators / Q000378:metabolism*; D005278:Fenitrothion / Q000633:toxicity*; D007306:Insecticides / Q000633:toxicity*; D011220:Pralidoxime Compounds / Q000378:metabolism; D013056:Spectrophotometry, Ultraviolet
chemical_list: D002800:Cholinesterase Inhibitors; D002801:Cholinesterase Reactivators; D007306:Insecticides; D011220:Pralidoxime Compounds; D000110:Acetylcholinesterase; C028797:pralidoxime; D005278:Fenitrothion