title: The effect of testosterone and rutting on the metabolism and pharmacokinetics of sulphadimidine in goats.
abstract: After testosterone pretreatment of castrated goats and during the rutting season of adult entire male goats, the oxidative metabolism of sulphadimidine (SDM) was inhibited markedly compared with the castrated control state of these animals. The oxidation of the 5 position (yielding 5-hydroxysulphadimidine) and of the 6-hydroxymethyl group (yielding 6-carboxysulphadimidine) was decreased equally, with that of the methyl group at the pyrimidine side chain itself being 6-hydroxymethylsulphadimidine (CH2OH), whereas the acetylation pathway was unaffected by testosterone. The consequence of altered metabolism by testosterone was a prolongation of SDM presence in the body. Effects on protein binding of the CH2OH metabolite and on the renal clearance of SDM were also investigated.
authors.affiliation: Faculty of Veterinary Medicine, Department of Veterinary Pharmacology, Pharmacy and Toxicology, Utrecht, The Netherlands.
authors.forename: J F
authors.initials: JF
authors.lastname: Nouws
authors.forename: B P
authors.initials: BP
authors.lastname: Meesen
authors.forename: H
authors.initials: H
authors.lastname: van Gogh
authors.forename: C
authors.initials: C
authors.lastname: Korstanje
authors.forename: A S
authors.initials: AS
authors.lastname: van Miert
authors.forename: T B
authors.initials: TB
authors.lastname: Vree
authors.forename: M
authors.initials: M
authors.lastname: Degen
mesh_terms: D000818:Animals; D006041:Goats / Q000378:metabolism*; D008297:Male; D009919:Orchiectomy; D011485:Protein Binding; D012726:Sexual Behavior, Animal; D013418:Sulfamethazine / Q000378:metabolism* / Q000493:pharmacokinetics; D013739:Testosterone / Q000494:pharmacology*
chemical_list: D013739:Testosterone; D013418:Sulfamethazine