甲硝唑结肠缓释片的药动学研究

 目的研究甲硝唑结肠缓释片的缓释特征和结肠靶向特征。方法采用家犬考察甲硝唑结肠缓释片口服后的血药浓度变化,并与甲硝唑普通片进行比较。采用大鼠口服受试药物,考察药物在大鼠消化道各段的释放情况。结果结肠缓释片的ρ_max为(4.94±2.79)mg·L^-1,t_max为(12.7±0.5)h,t_1/2β为(5.65±4.5)h,MRT为(16.65±5.1)h,AUC_0-τ为(36.09±12.81)mg·h·L^-1,AUC_0-∞为(37.63±11.92)mg·h·L^-1。与普通片比较,ρ_max显著降低,t_max显著延长,显示出缓释效果。大鼠口服甲硝唑结肠缓释片后主要在结肠段释放药物,在胃和其他肠段基本无药物释放。结论甲硝唑结肠缓释片具有结肠靶向和缓释的特征。

Pharmacokinetic Study of Metronidazole Colon-Specific Sustained-Release Tablets

OBJECTIVE To study the sustained-release and colon-specific characteristics of metronidazole colon-specific sustained-release tablets(MCST).METHODS The metronidazole concentrations in dog blood and the metronidazole content in each gastrointestinal segments were determined after an oral administration, the normal metronidazole tablet was as reference preparation.RESULTS The ρ_max of MCST was (4.94±2.79)mg·L^-1, the t_max and t_1/2β were (12.7±0.5) h and (5.65±4.5) h, MRT was (16.65±5.1) h;AUC_0-τ and AUC_0-∞ were (36.09±12.81) mg·h·L^-1 and (37.63±11.92) mg·h·L^-1, respectively. Compared with metronidazole normal tablets(MNT), the metronidazole colon-specific sustained-release tablet showed lower ρ_max and longer t_max which characterized sustained-release tablets. After the metronidazole colon-specific sustained-release tablets were administered to rats, metronidazole released mostly in colon with less in stomach and small intestine. CONCLUSION The sustained-release and colon-specific characteristics of metronidazole colon-specific sustained-release tablets were obvious.