title: Pharmacokinetic behaviour of albendazole sulphoxide enantiomers in male and female sheep.
abstract: Benzimidazole anthelmintic drugs are widely used in veterinary practice. Albendazole sulphoxide (ABZSO) is a benzimidazole drug with two enantiomers, as a consequence of a chiral centre in the sulphoxide group. The kinetics of these enantiomers were studied in male and female sheep. Plasma samples were obtained from the animals between 0.5 and 72 h after oral administration of 7.5 mg/kg of a racemic formulation of ABZSO (total-ABZSO). After a liquid-liquid extraction, the samples were analysed by HPLC to determine the concentrations of total-ABZSO and of the sulphone metabolite (ABZSO2). During the chromatographic analysis, the ABZSO peak was collected and reanalysed by an HPLC technique using a Chiral AGP column to quantify the enantiomeric proportion therein. After kinetic analysis, the AUCs obtained for the (+)-ABZSO were 5.8 and 4.0 times higher than those for the (-)-ABZSO in male and female animals, respectively. The mean residence times were 23.4 and 16.1 h for (+)-ABZSO and 22.2 and 17.4 h for (-)-ABZSO for male and female animals, respectively. The only significant difference between the sexes (p < 0.05) was in the Tmax of the (-)-ABZSO. Comparing both enantiomers within each sex, significant differences were found in all the kinetic parameters. Finally, no kinetic differences were found between sex for total-ABZSO or ABZSO2.
authors.affiliation: Departament de Farmacologia i de Terapèutica, Facultat de Veterinària, Bellaterra, Spain.
authors.forename: B P
authors.initials: BP
authors.lastname: Capece
authors.forename: G
authors.initials: G
authors.lastname: Castells
authors.forename: F
authors.initials: F
authors.lastname: Pérez
authors.forename: M
authors.initials: M
authors.lastname: Arboix
authors.forename: C
authors.initials: C
authors.lastname: Cristòfol
mesh_terms: D000284:Administration, Oral; D015766:Albendazole / Q000008:administration & dosage / Q000031:analogs & derivatives* / Q000097:blood / Q000493:pharmacokinetics; D000818:Animals; D000871:Anthelmintics / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics*; D019540:Area Under Curve; D002851:Chromatography, High Pressure Liquid / Q000662:veterinary; D005260:Female; D008297:Male; D012727:Sex Characteristics; D012756:Sheep / Q000378:metabolism*; D018709:Statistics, Nonparametric; D013237:Stereoisomerism
chemical_list: D000871:Anthelmintics; D015766:Albendazole; C027186:albendazole sulfoxide