title: Japanese quail acute exposure to methamidophos: experimental design, lethal, sub-lethal effects and cholinesterase biochemical and histochemical expression.
abstract: We exposed the Japanese quail (Coturnix coturnix japonica) to the organophosphate methamidophos using acute oral test. Mortality and sub-lethal effects were recorded in accordance to internationally accepted protocols. In addition cholinesterases were biochemically estimated in tissues of the quail: brain, liver and plasma. Furthermore, brain, liver and duodenum cryostat sections were processed for cholinesterase histochemistry using various substrates and inhibitors. Mortalities occurred mainly in the first 1-2h following application. Sub-lethal effects, such as ataxia, ruffled feathers, tremor, salivation and reduced or no reaction to external stimuli were observed. Biochemical analysis in the brain, liver and plasma indicates a strong cholinesterase dependent inhibition with respect to mortality and sub-lethal effects of the quail. The histochemical staining also indicated a strong cholinesterase inhibition in the organs examined and the analysis of the stained sections allowed for an estimation and interpretation of the intoxication effects of methamidophos, in combination with tissue morphology visible by Haematoxylin and Eosin staining. We conclude that the use of biochemistry and histochemistry for the biomarker cholinesterase, may constitute a significantly novel approach for understanding the results obtained by the acute oral test employed in order to assess the effects of methamidophos and other chemicals known to inhibit this very important nervous system enzyme.
authors.affiliation: Laboratory of Ecology and Environmental Sciences, Agricultural University of Athens, Iera Odos 75, Athens 11854, Greece. manousosf@yahoo.gr
authors.forename: Manousos
authors.initials: M
authors.lastname: Foudoulakis
authors.forename: Christos
authors.initials: C
authors.lastname: Balaskas
authors.forename: Attila
authors.initials: A
authors.lastname: Csato
authors.forename: Csaba
authors.initials: C
authors.lastname: Szentes
authors.forename: Gerassimos
authors.initials: G
authors.lastname: Arapis
mesh_terms: D000818:Animals; D002800:Cholinesterase Inhibitors / Q000097:blood / Q000493:pharmacokinetics / Q000633:toxicity*; D002802:Cholinesterases / Q000378:metabolism*; D003370:Coturnix / Q000097:blood / Q000254:growth & development / Q000378:metabolism; D004305:Dose-Response Relationship, Drug; D004784:Environmental Monitoring / Q000379:methods*; D004785:Environmental Pollutants / Q000097:blood / Q000493:pharmacokinetics / Q000633:toxicity*; D009928:Organ Specificity; D009946:Organothiophosphorus Compounds / Q000097:blood / Q000493:pharmacokinetics / Q000633:toxicity*; D012107:Research Design; D016019:Survival Analysis; D014018:Tissue Distribution
chemical_list: D002800:Cholinesterase Inhibitors; D004785:Environmental Pollutants; D009946:Organothiophosphorus Compounds; C014655:methamidophos; D002802:Cholinesterases