肝靶向去甲斑蝥素微乳的研究

目的考察去甲斑蝥素(NCTD)微乳的形态、粒径分布及生物安全性，研究去甲斑蝥素微乳及其注射液在小鼠体内的组织分布、药代动力学和体外药效学。方法用气相法测定小鼠体内去甲斑蝥素含量。数据用3P87处理，得到各主要药代动力学参数。采用体外细胞毒性和体内全身急性毒性试验方法，评价去甲斑蝥素微乳的抗肿瘤活性及其生物安全性。结果微乳平均粒径为(44±9) nm。血浆中成分及制剂中辅料不干扰去甲斑蝥素测定。小鼠静脉注射去甲斑蝥素微乳及其去甲斑蝥素注射液后的药-时曲线均符合二室模型。去甲斑蝥素微乳的药代动力学研究表明，在同剂量条件下，NCTD微乳可在体内较长时间保持较高浓度，即可在一定程度上延长体内循环时间；微乳及注射液的AUC，MRT，T_1/2分别为(29.7±0.9)，(9.25±0.09) mg·h·L^-1，(110±11)，(86.7±0.8)，(103±12)，(42±4) h，NCTD微乳改变NCTD注射剂在小鼠体内的药时曲线和血药浓度的高低，其消除T_1/2和MRT比其注射剂分别增加了2.48和1.27倍，AUC增加了3.21倍；NCTD微乳在肝、肾中的靶向指数分别为0.43和0.12。去甲斑蝥素微乳的生物安全性与其市售注射液比较无显著性差异。结论去甲斑蝥素微乳较去甲斑蝥素注射液增强了药物的肝靶向性，降低了肾脏分布，在一定程度上延长药物在小鼠体内的循环时间。

Studies on the liver targeting of norcantharindin microemulsion

AIM: To study the morphology, particle size distribution and biological reliability of the norcantharindin (NCTD)-loaded microemulsion and pharmacokinetics of the W/O norcantharidin-loaded microemulsion in mice. METHODS: The concentration of NCTD in plasma and tissues were determined by GC method. The data obtained were processed using 3P87 program. RESULTS: The mean particle diameter of microemulsion was (44 +/- 9) nm. The concentration-time curve of NCTD-loaded microemulsion and NCTD injection was fitted to a two-compartment model. At the same dosage, the pharmacokinetic study for NCTD-loaded microemulsion showed the NCTD microemulsion had relatively longer circulating time in mice. Area under the curve of concentration versus time (AUC), mean residence time (MRT) and half life (T1/2) for microemulsion and injection were (29.7 +/- 0.9) mg x h x L(-1), (9.25 +/- 0.09) mg x h x L(-1), (110 +/- 11) h, (86.7 +/- 0.8) h, (103 +/- 12) h, (42 +/- 4) h, respectively. Targeting index of NCTD microemulsion in liver and kidney in mice were 0.43 and 0.12 after iv NCTD-loaded microemulsion. The effects of biological reliability was not significantly different between NCTD microemulsion and NCTD injection in vivo and in vitro. CONCLUSION: The liver targeting absorptive capability of NCTD-loaded microemulsion was enhanced and the release time was extended compared with NCTD injection. While the microemulsion vehicles could decrease the kidney distribution of NCTD.