Submitted to: Environmental Toxicology and Pharmacology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 10/12/2004
Publication Date: 10/1/2005
Citation: Lee, S., Campbell, B.C., Ok, Y., Kim, J., Park, B., Liu, N. 2005. Biochemical changes in dehydrogenase, hydroxylase and tyrosinase of a permethrin-resistant strain of housefly larvae, musca domestica l. Environmental Toxicology and Pharmacology.20(2):258-263. Interpretive Summary:
Technical Abstract: Permethrin-resistant (ALHF) and susceptible (aabys) strains of housefly were used to understand enzymic changes in biosynthetic pathways after insecticide selection. Aflatoxin B1 (AFB1) as a natural substrate was used to verify the changes in cytochrome P450-dependent monooxygenases and oxido-reductase activities. Three major biotransformation products were found: aflatoxin B2a (AFB2a), aflatoxin M1 (AFM1), and aflatoxicol (AFL) in both strains. AFL production was 5-fold lower in the resistant v. susceptible strain. The levels of 17a- and b-hydroxysteroid dehydrogenase (17a- and b-HSD) were also determined to elucidate which type of dehydrogenase activities could be changed. ALHF larvae yielded about 2-fold higher 17a-estradiol than that of aabys larvae and 2-fold lower amount of 17a-estradiol than that of aabys larvae. in cytosolic and microsomal fractions, respectively. Production rate of tyrosine from phenylalanine in ALHF was about 2-fold higher than in aabys. In summary, enzymic changes were found that may result from the permethrin selection.