Phenylpyrazole Insecticide Photochemistry, Metabolism, and GABAergic Action: Ethiprole Compared with Fipronil
- 15 October 2003
- journal article
- research article
- Published by American Chemical Society (ACS) in Journal of Agricultural and Food Chemistry
- Vol. 51 (24) , 7055-7061
- https://doi.org/10.1021/jf030439l
Abstract
Ethiprole differs from fipronil, the major phenylpyrazole insecticide, only in an ethylsulfinyl substituent replacing the trifluoromethylsulfinyl moiety. This study compares their photochemistry, metabolism, action at the γ-aminobutyric acid (GABA) receptor, and insecticidal potency. On exposure to sunlight as a thin film, ethiprole undergoes oxidation (major), reduction, and desethylsulfinylation but not desulfinylation whereas the major photoreaction for fipronil is desulfinylation. Metabolic sulfone formation is more rapid with ethiprole than fipronil in human expressed CYP3A4 in vitro and mouse brain and liver in vivo. High biological activity is observed for the sulfide, sulfoxide, sulfone, and desulfinyl derivatives in both the ethiprole and the fipronil series in GABA receptor assays (human recombinant β3 homomer and house fly head membranes) with [3H]EBOB and in topical toxicity to house flies with and without the P450-inhibiting synergist piperonyl butoxide. On an overall basis, the ethiprole series is very similar in potency to the fipronil series. Keywords: Ethiprole; fipronil; GABA receptor; metabolism; phenylpyrazole insecticide; photochemistryKeywords
This publication has 12 references indexed in Scilit:
- Efficacy of ethiprole applied alone and in combination with conventional insecticides for protection of stored wheat and stored corn.Journal of Economic Entomology, 2002
- Synthesis of fipronil sulfide, an active metabolite, from the parent insecticide fipronilTetrahedron Letters, 2001
- GABA receptor subunit composition relative to insecticide potency and selectivityToxicology Letters, 2001
- Role of Human GABAA Receptor β3 Subunit in Insecticide ToxicityToxicology and Applied Pharmacology, 2001
- Control of fleas on naturally infested dogs and cats and in private residences with topical spot applications of fipronil or imidaclopridVeterinary Parasitology, 2000
- CYTOCHROME P-450 3A4: Regulation and Role in Drug MetabolismAnnual Review of Pharmacology and Toxicology, 1999
- Mechanisms for Selective Toxicity of Fipronil Insecticide and Its Sulfone Metabolite and Desulfinyl PhotoproductChemical Research in Toxicology, 1998
- Fipronil insecticide: Novel photochemical desulfinylation with retention of neurotoxicityProceedings of the National Academy of Sciences, 1996
- Insecticide action at the GABA‐gated chloride channel: Recognition, progress, and prospectsArchives of Insect Biochemistry and Physiology, 1993
- House fly brain γ-aminobutyric acid-gated chloride channel: target for multiple classes of insecticidesPesticide Biochemistry and Physiology, 1991