莱克多巴胺在兔体内的药物动力学及生物利用度研究

The Pharmacokinetics and Bioavailability of Ractopamine in Rabbits

关键词:  莱克多巴胺  药物动力学  兔  绝对生物利用度

Key words:  ractopamine  pharmacokinetics  rabbit  bioavailability

摘要:

研究莱克多巴胺静脉注射和灌胃在兔体内的药动学特征和生物利用度,静脉注射和灌胃的给药剂量分别为10 mg.kg-1和20 mg.kg-1。兔静脉注射莱克多巴胺溶液的药-时数据符合无吸收两室模型,主要药动学参数分别为T1/2α 0.56 ± 0.084 h、T1/2β 7.20 ± 0.59 h、AUC 8.04 ± 2.32 h.μg.mL-1。兔灌胃莱克多巴胺溶液的药时数据符合一级吸收两室模型,主要药动学参数分别为TK01 0.72 ± 0.07 h、T1/2α 0.72 ± 0.11 h、T1/2β 26.43 ± 2.73 h、Tmax 1.13 ± 0.09 h、Cmax 1.29 ± 0.08 μg.mL-1、AUC 3.98 ± 0.43 h.μg.mL-1。灌服莱克多巴胺溶液的绝对生物利用度F为24%。莱克多巴胺在兔体内的药动学特征是吸收迅速，分布广泛，消除缓慢，生物利用度低。

Abstract:

The pharmacokinetics and bioavailability of ractopamine were investigated in rabbits following single intravenous (10 mg.kg-1), oral (20 mg.kg-1) administration of ractopamine solution. The ractopamine concentration-time data were fitted to a two-compartment model after single intravenous administration of the ractopamine solution. The main pharmacokinetic parameters were as follows: T1/2α 0.56 ± 0.084 h、T1/2β 7.20 ± 0.59 h、AUC 8.04 ± 2.32 h.μg.mL-1. The ractopamine concentration-time data were described by a two-compartment model with first-order absorption after single oral administration of the ractopamine solution. The main pharmacokinetic parameters were as follows, respectively: TK01 0.72 ± 0.07 h、T1/2α 0.72 ± 0.11 h、T1/2β 26.43 ± 2.73 h、Tmax 1.13 ± 0.09 h、Cmax 1.29 ± 0.08 μg.mL-1、AUC 3.98 ± 0.43 h.μg.mL-1. The intragastric bioavailability of ractopamine solution was 24%.The pharmacokinetic characteristics of ractopamine in rabbit displayed rapid absorption, slow elimination and low bioavailability.