title: Disposition of human drug preparations in the horse. V. Orally administered oxprenolol.
abstract: Urinary concentrations of the beta-antagonist oxprenolol and some of its major human metabolites were determined following oral administration of a dose of 160 mg to five fasted horses. Quantitation was performed by gas chromatography-mass spectrometry (GC-MS) in the selected ion mode (SIM) by monitoring ion m/z 466 of the heptafluorobutyric derivatives. As early as 2 h after dosage oxprenolol could be detected in hydrolysed urine and remained detectable up to 24 h. Maximum urinary concentrations and excretion rates were obtained between 2 and 12 h. After 12 h only 2.8% of the administered dose was excreted as conjugates of oxprenolol and major human metabolites including 4-OH-oxprenolol and 5-OH-oxprenolol. These metabolites were detectable up to 48 h.
authors.affiliation: Vakgroep Farmacologie, Farmacie en Toxicologie, Faculteit Diergeneeskunde, Universiteit Gent, Merelbeke, Belgium.
authors.forename: F T
authors.initials: FT
authors.lastname: Delbeke
mesh_terms: D000284:Administration, Oral; D000319:Adrenergic beta-Antagonists / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics* / Q000652:urine; D000818:Animals; D001192:Arylsulfatases / Q000378:metabolism; D005215:Fasting; D005260:Female; D005466:Fluorocarbons / Q000737:chemistry; D008401:Gas Chromatography-Mass Spectrometry / Q000662:veterinary; D005966:Glucuronidase / Q000378:metabolism; D006736:Horses / Q000378:metabolism*; D006801:Humans; D006868:Hydrolysis; D007202:Indicators and Reagents / Q000737:chemistry; D010096:Oxprenolol / Q000008:administration & dosage / Q000737:chemistry / Q000493:pharmacokinetics* / Q000652:urine; D012016:Reference Values
chemical_list: D000319:Adrenergic beta-Antagonists; D005466:Fluorocarbons; D007202:Indicators and Reagents; C007924:heptafluorobutyric anhydride; D010096:Oxprenolol; D001192:Arylsulfatases; D005966:Glucuronidase