五水头孢唑林钠与头孢唑林钠在兔体内的药动学比较

目的:比较五水头孢唑林钠和头孢唑林钠在兔体内的药动学差异。方法:取兔随机分为两组,每组6只,分别耳缘静脉注射五水头孢唑林钠和头孢唑林钠200 mg/kg(以头孢唑林钠计),分别于给药前和给药后5、15、25、35、65、95、125、155、215、275、335 min耳缘静脉取血甲醇沉淀血浆蛋白后,高效液相色谱法测定血药浓度,间隔1周后进行交叉实验;采用3p97软件计算药动学参数。结果:五水头孢唑林钠和头孢唑林钠在兔体内的药动学特征均符合二室模型,主要药动学参数分别为t1/2α:18.46、16.06 min,t1/2β:40.85、55.12 min,AUC0-335 min:20 635.30、35 056.86μg·min/ml,CL:0.009 7、0.005 7 L·kg/h;五水头孢唑林钠的相对生物利用度为58.86%,五水头孢唑林钠的AUC0-335 min对数90%置信区间为头孢唑林钠相应参数的95.47%¹06.55%。结论:与头孢唑林钠比较,五水头孢唑林钠在兔体内的消除更快、生物利用度较低,二者生物学不等效。

Comparison of the Pharmacokinetics of Cefazolin Sodium Pentahydrate vs. Cefazolin Sodium in Rabbits

OBJECTIVE：To compare the pharmacokinetics of cefazolin sodium and cefazolin sodium pentahydrate in rabbits.METHODS：Rabbits were randomized into 2 groups with 6 rabbits. The rabbit ear vein were injected with cefazolin sodium pentahydrate or cefazolin sodium 200 mg/kg（by cefazolin sodium）. The blood sample was collected before medication and 5,15,25,35,65,95,125,155,215,275 and 335 min after medication respectively. After the plasma sample deproteinized with methanol,the plasma concentration was determined by HPLC. Cross test was performed every 1 week. 3p97 software was used to calculate pharmacokinetic parameters. RESULTS：Cefazolin sodium pentahydrate and cefazolin sodium are both two-compartment models.Pharmacokinetic parameters of them were as follows：t1/2αof 18.46 min vs. 16.06 min,t1/2βof 40.85 min vs. 55.12 min,AUC0-335 min of 20 635.30 μg·min/ml vs. 35 056.86 μg·min/ml;CL of 0.009 7 L·kg/min vs. 0.005 7 L·kg/h. Relative bioavailability of cefazolin sodium pentahydrate was 58.86%. 90% CI of AUC0-335 minlogarithmic of cefazolin sodium pentahydrate was 95.47%-106.55% of that of cefazolin sodium. CONCLUSIONS：Compared with cefazolin sodium,cefazolin sodium pentahydrate removes more rapidly in rabbits and has lower bioavailability. Cefazolin sodium and cefazolin sodium pentahydrate are not bioequivalent.