title: Ovine urinary metabolites of ethoxyquin.
abstract: Metabolites of ethoxyquin (EQ, 1,2-dihydro-6-ethoxy-2,2,4-trimethylquinoline) in the urine of sheep and rats were separated and identified by gas chromatography-mass spectrometry (GC-MS). Sheep were given diets containing EQ or EQ.HCl (0.5% of total diet) and urine samples were collected for the first 24 h and for another 24-h period after 12 d of feeding. Rats were given EQ/corn oil (0.08 g EQ/d/rat) orally for 7 d and urine samples were collected at ambient temperature for a 24-h period following 6 d of dosing. The urine samples were extracted with ethyl acetate at pH 5, and the concentrated extracts were analyzed by GC-MS. Ethoxyquin was identified in all sheep urine samples collected during the first 24 h of feeding, and EQ and hydroxylated EQ were identified in all urine samples collected after 12 d of feeding. In contrast, EQ, hydroxylated EQ, and dihydroxylated EQ were identified in urine collected from rats fed EQ for 7 d.
authors.affiliation: Department of Veterinary Physiology and Pharmacology, Texas A&M University, College Station 77843.
authors.forename: H L
authors.initials: HL
authors.lastname: Kim
authors.forename: A C
authors.initials: AC
authors.lastname: Ray
authors.forename: M C
authors.initials: MC
authors.lastname: Calhoun
mesh_terms: D000284:Administration, Oral; D000821:Animal Feed; D000818:Animals; D005015:Ethoxyquin / Q000008:administration & dosage / Q000493:pharmacokinetics / Q000652:urine*; D008401:Gas Chromatography-Mass Spectrometry; D008297:Male; D011897:Random Allocation; D051381:Rats; D017208:Rats, Wistar; D012756:Sheep / Q000378:metabolism / Q000652:urine*
chemical_list: D005015:Ethoxyquin