title: Toxicity and characterization of cholinesterase-inhibition induced by diisopropyl fluorophosphate in Artemia salina larvae.
abstract: The acute toxicity of diisopropyl fluorophosphate (DFP) on three age classes of Artemia salina was evaluated. An increase in toxicity of this organophosphorous (OP) compound was found following longer development of A. salina larvae. The effects of pretreatment with the non-selective muscarinic antagonist atropine, the two reversible acetylcholinesterase inhibitors physostigmine and pyridostigmine, and the cholinesterase-reactivating oxime 2-pyridine aldoxime methoiodide (2-PAM), as individual and combined pretreatments, on DFP-induced lethality in 24h Artemia were also investigated. The lethal action of DFP was not prevented by pretreatment of 24h Artemia with atropine, physostigmine, and pyridostigmine, while 2-PAM proved effective against intoxication with this OP compound. The inhibitory effects of combinations of atropine (10(-5)M) plus 2-PAM or physostigmine were greater than those elicited by either drug alone, with the maximum protection afforded being 100%. Pretreatment with 2-PAM (10(-6)M) plus physostigmine or pyridostigmine was ineffective. These results suggest that the combinations of atropine plus 2-PAM or physostigmine are effective in the prevention of the lethal effects induced by DFP in A. salina larvae.
authors.affiliation: Departamento de Toxicología y Farmacología, Facultad de Veterinaria, Universidad Complutense de Madrid, Avda. Puerta de Hierro, s/n, 28040 Madrid, Spain.
authors.forename: S
authors.initials: S
authors.lastname: Sánchez-Fortún
authors.forename: M V
authors.initials: MV
authors.lastname: Barahona
mesh_terms: D000818:Animals; D001156:Artemia / Q000187:drug effects* / Q000502:physiology; D001285:Atropine / Q000494:pharmacology; D002800:Cholinesterase Inhibitors / Q000633:toxicity*; D002801:Cholinesterase Reactivators / Q000494:pharmacology; D004359:Drug Therapy, Combination; D007531:Isoflurophate / Q000037:antagonists & inhibitors / Q000633:toxicity*; D007814:Larva / Q000187:drug effects* / Q000201:enzymology; D008136:Longevity / Q000187:drug effects; D018727:Muscarinic Antagonists / Q000494:pharmacology; D010830:Physostigmine / Q000633:toxicity; D011220:Pralidoxime Compounds / Q000494:pharmacology; D011729:Pyridostigmine Bromide / Q000633:toxicity; D023382:Toxicity Tests, Acute; D014874:Water Pollutants, Chemical / Q000037:antagonists & inhibitors / Q000633:toxicity*
chemical_list: D002800:Cholinesterase Inhibitors; D002801:Cholinesterase Reactivators; D018727:Muscarinic Antagonists; D011220:Pralidoxime Compounds; D014874:Water Pollutants, Chemical; D007531:Isoflurophate; D001285:Atropine; D010830:Physostigmine; D011729:Pyridostigmine Bromide; C028797:pralidoxime