恩诺沙星在红笛鲷体内的药代动力学

在水温26±2℃、盐度28条件下,恩诺沙星(enrofloxacin,EF)按5 mg/kg的剂量腹腔注射和口灌红笛鲷(Lutjanus sanguineus),用反相高效液相色谱法研究恩诺沙星在红笛鲷体内的药代动力学和组织分布。结果显示:注射和口灌后红笛鲷血浆的药时数据均符合一级吸收二室模型;血药达峰时间(tp)分别为0.75和1.5 h,血药质量浓度峰值(cmax)分别为5.22和3.94μg/mL,药时曲线下面积(AUC)分别36.98和17.24 mg/(L.h),消除半衰期(t1/2β)分别为13.28和9.18 h;恩诺沙星在组织中分布较广,注射和灌服给药肌肉、肝脏和肾脏的cmax分别为3.53和3.40μg/g、4.08和3.98μg/g、11.23和5.40μg/g,tp分别为1.5和2.0 h、1.0和2.0 h、0.75和1.5 h,AUC分别33.17和23.12 mg/(L.h)、39.36和18.20 mg/(L.h)、98.97和56.69 mg/(L.h);EF在红笛鲷体内消除速度较慢,注射和灌服给药肌肉、肝脏和肾脏的t1/2β分别为22.08和83.32 h、41.52和94.47 h、20.94和21.81 h。表明恩诺沙星注射给药在红笛鲷体内的吸收和消除均快于口灌给药。

Pharmacokinetics of Enrofloxacin in Lutjanus sanguineus

The pharmacokinetics of enrofloxacin（EF） were investigated with a single dose of 5mg/kg body weight after peritoneal injection and oral administration in Lutjanus sanguineus at the water temperature of 26±2 ℃ and salinity of 28.Plasma and tissue concentrations of EF were simultaneously detected by the RP-HPLC.The results showed that EF concentration-time data in plasma of L.sanguineus following two different forms of administration were described as a two-compartment model with first-order absorption.The time of peak concentration（tP）were 0.75 and 1.5 h,and the maximum EF concentration（cmax） were 5.22 and 3.94 μg/mL,and the area under the concentration-time curve（AUC） were 36.98 and 17.24 mg/（L.h）,and the elimination half-life（t1/2β） were 13.28 and 9.18 h.The present results indicated that enrofloxacin in L.sanguineus after peritoneal injection and oral administration had the ability to distribute widely to diverse tissues.cmax of muscle,liver and kidney were 3.53 and 3.40 μg/g,4.08 and 3.98 μg/g,11.23 and 5.40 μg/g,and tp were 1.5 and 2.0 h,1.0 and 2.0 h,0.75 and 1.5 h,and AUC were 33.17 and 23.12 mg/（L.h）,39.36 and 18.20 mg/（L.h）,98.97 and 56.69 mg/（L.h）,respectively.Enrofloxacin eliminated slowly,and t1/2β of muscle,liver and kidney were 22.08 and 83.32 h,41.52 and 94.47 h,20.94 and 21.81 h,respectively.These results indicated the quicker absorption and faster elimination after peritoneal injection administration than that after oral administration.