替诺福韦、依非韦伦对拉米夫定在大鼠体内药动学的影响

Effect of tenofovir and efavirenz on the pharmacokinetics of lamivudine in rats

目的 建立一种快速、灵敏的UFLC-MS/MS方法测定大鼠血浆中拉米夫定的浓度,并研究联合给予富马酸替诺福韦酯、依非韦伦对拉米夫定在大鼠体内血浆药动学的影响。方法 以阿昔洛韦为内标,采用96孔板甲醇蛋白沉淀法处理血浆样品。采用Agilent ZORBAX SB-Aq色谱柱(4.6 mm×150 mm,5 μm)进行分离,以水(含25 mmol·L^(-1)乙酸铵+0.1%甲酸)-甲醇为流动相,流速1 mL·min^(-1),3∶7分流,梯度洗脱。采用电喷雾离子源(ESI),正离子模式下检测。将12只SD大鼠随机分为单独给药组(拉米夫定 32 mg·kg^(-1))和联合给药组(拉米夫定 32 mg·kg^(-1)+富马酸替诺福韦酯 21 mg·kg^(-1)+依非韦伦 43 mg·kg^(-1)),每组6只,雌雄各半,给药后于不同时间点采集血样,测定拉米夫定的血药浓度。采用DAS 2.0软件以非房室模型计算药动学参数,并进行统计学分析。结果 拉米夫定在10.26~2052 ng·mL^(-1)与峰面积呈现良好的线性关系(r=0.9995),日内和日间精密度均小于10%,准确度为92.23%~103.10%。与单独给药组相比,联合给药组拉米夫定的药动学参数C_(max)、t_(max)、t_(1/2)及AUC_(0~∞)差异均无统计学意义。结论 建立的UFLC-MS/MS法快速、灵敏、专属性强,适用于大鼠血浆中拉米夫定浓度的测定。单剂量给药富马酸替诺福韦酯、依非韦伦对拉米夫定在大鼠体内的药动学行为无明显影响,提示联用后不存在显著的药动学相互作用。

Objective To develop a sensitive and rapid UFLC-MS/MS method for the quantitative determination of lamivudine in rat plasma,and to determine the potential effect of tenofovir disoproxil fumarate and efavirenz on the pharmacokinetics of lamivudine.Methods Plasma samples were pretreated by methanol on 96-well plates and acyclovir was selected as the internal standard.The chromatographic separation was conducted on an Agilent ZORBAX SB-Aq column (4.6 mm×150 mm,5 μm) with gradient elution of 25 mmol·L^(-1) ammonium acetate solution containing 0.1% formic acid and methanol.The flow rate was 1 mL·min^(-1) and 30% of post-column eluent was injected into the mass spectrometer,equipped with electrospray ionization (ESI) source under positive mode.Totally 12 rats were randomized into 2 groups (3 males and 3 females rats in each group).Rats in group A were orally administered lamivudine (32 mg·kg^(-1)),while those in group B were orally administered lamivudine (32 mg·kg^(-1)),tenofovir disoproxil fumarate (21 mg·kg^(-1)) and efavirenz (43 mg·kg^(-1)) in combination.Blood samples were collected at different time points after the drug administration and the plasma concentrations of lamivudine were determined.The pharmacokinetic parameters were calculated with DAS 2.0 software in a non-compartmental model.Results Lamivudine showed excellent linearity at 10.26~2052 ng·mL^(-1) (r=0.9995).The intra-and inter-day precisions were less than 10% and the accuracy ranged from 92.23% to 103.10%.There was no statistical significance in the pharmacokinetic parameters of lamivudine between both groups,such as C_(max),t_(max),t_(1/2),and AUC_(0~∞).Conclusion The established UFLC-MS/MS method is fast,sensitive and robust,and is suitable for the determination of lamivudine in the rat plasma.Single-dose administration of tenofovir disoproxil fumarate and efavirenz has no significant effect on the pharmacokinetic behaviors of lamivudine in rats,indicating no pharmacokinetic interaction after the administration in combination.