Dyke T M, Sams R A, Hinchcliff K W
Analytical Toxicology Laboratory, College of Veterinary Medicine, Ohio State University, Columbus 43210-1089, USA.
Am J Vet Res. 1998 Mar;59(3):280-5.
To measure renal clearance of antipyrine and urinary excretion of antipyrine (AP) metabolites in horses by use of validated high-performance liquid chromatography (HPLC) methods.
8 Standardbred mares.
HPLC methods for measurement of AP in equine plasma and AP and its metabolites in equine urine were validated. Antipyrine (20 mg/kg of body weight) was administered i.v., and blood samples and urine specimens were collected over 24 hours.
Median plasma clearance of AP in horses was 6.2 ml/min/kg, of which < 2% could be attributed to renal clearance. Urinary excretion of AP and its metabolites over 24 hours accounted for < 22% of the AP dose administered. The major metabolite of AP in urine was 4-hydroxyantipyrine.
Use of the proven validated methods for measuring AP and its metabolites indicated that AP has minimal renal clearance in horses, suggesting that plasma clearance of AP reflects hepatic clearance. Combined with AP metabolite data, the pharmacokinetics of AP may be useful for assessment of hepatic cytochrome P450 activity in horses.
采用经验证的高效液相色谱（HPLC）方法测定马体内安替比林的肾清除率及安替比林（AP）代谢物的尿排泄量。
8匹标准赛马母马。
对测定马血浆中AP以及马尿液中AP及其代谢物的HPLC方法进行验证。静脉注射安替比林（20 mg/kg体重），并在24小时内采集血样和尿样。
马体内AP的血浆清除率中位数为6.2 ml/（min·kg），其中肾清除率占比不到2%。24小时内AP及其代谢物的尿排泄量占给药剂量的比例不到22%。尿液中AP的主要代谢物为4-羟基安替比林。
使用经证实有效的方法测定AP及其代谢物表明，AP在马体内的肾清除率极低，提示AP的血浆清除率反映的是肝脏清除率。结合AP代谢物数据，AP的药代动力学可能有助于评估马体内肝细胞色素P450的活性。
