title: Depletion of protein-bound furazolidone metabolites containing the 3-amino-2-oxazolidinone side-chain from liver, kidney and muscle tissues from pigs.
abstract: Ten 3-month-old pigs were treated with feed containing 300 mg furazolidone per kg for a period of 7 days, followed by withdrawal periods of 0, 1, 2, 3 or 4 weeks (two per group). The treatment resulted in the formation of protein-bound metabolites containing an intact 3-amino-2-oxazolidinone (AOZ) side-chain that could be chemically released and then detected in liver, kidney and rump muscle tissues even 4 weeks after dosing. In tissues from animals killed at the end of the medication period, 993, 600 and 124 ng of AOZ were released from 1 g of liver, kidney and muscle respectively. In the tissues of the animals killed after a further 4 weeks the corresponding levels were 41, 7 and 10 ng/g respectively. It may be concluded that long withdrawal periods prior to slaughter for human consumption are required for pigs treated with furazolidone, because of the long residence time of protein-bound AOZ and the possibility that it might be released from its protein-bound form in the stomach and subsequently be transformed into a hydrazine.
authors.affiliation: State Institute for Quality Control of Agricultural Products (RIKILT-DLO), Wageningen, The Netherlands.
authors.forename: L A
authors.initials: LA
authors.lastname: Hoogenboom
authors.forename: M C
authors.initials: MC
authors.lastname: Berghmans
authors.forename: T H
authors.initials: TH
authors.lastname: Polman
authors.forename: R
authors.initials: R
authors.lastname: Parker
authors.forename: I C
authors.initials: IC
authors.lastname: Shaw
mesh_terms: D000818:Animals; D004350:Drug Residues / Q000032:analysis; D005506:Food Contamination; D005664:Furazolidone / Q000378:metabolism* / Q000493:pharmacokinetics; D007668:Kidney / Q000737:chemistry*; D008099:Liver / Q000737:chemistry*; D009132:Muscles / Q000737:chemistry*; D010080:Oxazoles / Q000032:analysis*; D023303:Oxazolidinones; D013552:Swine
chemical_list: D010080:Oxazoles; D023303:Oxazolidinones; D005664:Furazolidone; C000209:3-amino-2-oxazolidinone