title: The effects of fenvalerate on hepatic and cerebral xenobiotic metabolizing enzymes in selenium and/or iodine deficient rats.
abstract: OBJECTIVE
  Particularly in developing countries, selenium and/or iodine deficiencies are encountered and use of pesticides in agriculture are not well-controlled. Fenvalerate is a pyrethroid insectide used in agriculture and has applications against a wide range of pests. This study was designed to evaluate the effects of fenvalerate on hepatic and cerebral xenobiotic metabolizing enzyme activities in the presence of iodine and/or selenium deficiency on a rat model.
  
  
  METHODS
  Iodine and/or selenium deficiency was induced by feeding three-week-old Wistar rats with a diet containing <0.005 mg selenium kg-1, and/or administering 1% sodium perchlorate in drinking water for 7 weeks. Test groups received fenvalerate (100 mg kg-1 BW IP) for the last 7 days. Hepatic and cerebral microsomal aniline hydroxylase (CYP2E1) and cytosolic glutathione S-transferase (GST) activities were determined. Besides, hepatic NADPH-cytochrome P450 reductase (P450R), ethoxyresorufin O-deethylase (EROD, CYP1A1/1A2) and penthoxyresorufin O-depenthylase (PROD, CYP2B1/2B2), activities were also measured.
  
  
  RESULTS
  Fenvalerate had a general inductive effect on the hepatic and cerebral xenobiotic metabolizing enzyme activities. Moreover, enzyme activities were also altered by iodine and/or selenium deficiency, but the effects seemed to be enzyme- and tissue-specific.
  
  
  CONCLUSIONS
  The inductive effect of fenvalerate, particularly in high dose exposures, may change the metabolism of several xenobiotics, including drugs, as well as endogenous substrates. The effects may vary depending on the selenium and/or iodine status of individual.
authors.affiliation: Hacettepe University, Faculty of Pharmacy, Department of Toxicology, Ankara 06100 Turkey.
authors.forename: Aydan
authors.initials: A
authors.lastname: Caglayan
authors.affiliation: Hacettepe University, Faculty of Pharmacy, Department of Toxicology, Ankara 06100 Turkey.
authors.forename: Belma
authors.initials: B
authors.lastname: Kocer-Gumusel
authors.affiliation: Hacettepe University, Faculty of Pharmacy, Department of Toxicology, Ankara 06100 Turkey.
authors.forename: Pinar
authors.initials: P
authors.lastname: Erkekoglu
authors.affiliation: Hacettepe University, Faculty of Pharmacy, Department of Toxicology, Ankara 06100 Turkey.
authors.forename: Filiz
authors.initials: F
authors.lastname: Hincal
keywords: Fenvalerate; Iodine; Selenium; Thyroid hormones; Xenobiotic metabolizing - enzymes