title: Induction of cytochrome P-450 activity in individual Chironomus riparius Meigen larvae exposed to xenobiotics.
abstract: Cytochrome P450 activity in individual Chironomus riparius larvae was measured using a microtiter plate adaptation of the ethoxyresorufin-O-deethylase (EROD) assay. The sensitivity of this biomarker was tested by exposing larvae to phenobarbital (0.5 and 1.0 mM) and permethrin (1 and 10 microg/g). Both chemicals induced EROD activity in C. riparius larvae by up to 1.58-fold with PB and 2.47-fold with permethrin. EROD induction was more pronounced after 48 h. The initially high EROD activity in the controls suggested that P450s are induced by stress. Feeding levels prior to exposure also had a significant effect on EROD activity. EROD activity compared to the control was highest when larvae were fed double the normal ration. These results indicate that EROD activity in individual C. riparius may be a useful biomarker to add to a suite of biomarkers for the detection of freshwater pollution.
authors.affiliation: Ecotoxicology Research Group, Division of Zoology, School of Animal and Microbial Sciences, The University of Reading, Whiteknights PO Box 228, Reading RG6 6AJ, UK.
authors.forename: Thomas
authors.initials: T
authors.lastname: Fisher
authors.forename: Mark
authors.initials: M
authors.lastname: Crane
authors.forename: Amanda
authors.initials: A
authors.lastname: Callaghan
mesh_terms: D000818:Animals; D001681:Biological Assay; D015415:Biomarkers / Q000032:analysis; D002683:Chironomidae / Q000201:enzymology*; D019363:Cytochrome P-450 CYP1A1 / Q000032:analysis / Q000494:pharmacology; D003577:Cytochrome P-450 Enzyme System / Q000494:pharmacology*; D004781:Environmental Exposure; D004790:Enzyme Induction; D006993:Hypnotics and Sedatives / Q000009:adverse effects; D007306:Insecticides / Q000009:adverse effects; D007814:Larva / Q000201:enzymology; D026023:Permethrin / Q000009:adverse effects; D010634:Phenobarbital / Q000009:adverse effects; D014873:Water Pollutants / Q000009:adverse effects*; D015262:Xenobiotics / Q000009:adverse effects
chemical_list: D015415:Biomarkers; D006993:Hypnotics and Sedatives; D007306:Insecticides; D014873:Water Pollutants; D015262:Xenobiotics; D026023:Permethrin; D003577:Cytochrome P-450 Enzyme System; D019363:Cytochrome P-450 CYP1A1; D010634:Phenobarbital