黄芩苷和黄芩素大鼠在体胃、肠的吸收动力学研究

Studies on the absorption kinetics of baicalin and baicalein in rats' stomachs and intestines

目的:研究黄芩苷和黄芩素在大鼠胃、肠的吸收动力学特征。方法:采用大鼠在体胃、肠吸收模型,以高效液相色谱法测定胃、肠灌注液中药物的含量。结果:黄芩苷在胃、小肠及结肠中的每小时吸收率分别为8.05%,-0.94%,2.32%;黄芩素在胃、小肠及结肠中的每小时吸收率分别为34.53%,30.61%,4.89%。黄芩素在十二指肠、空肠、回肠及结肠的每小时吸收速率常数分别为0.090 7,0.083 7,0.076 6,0.048 3。结论:黄芩苷只在胃中有一定程度的吸收,在小肠和结肠基本不吸收;黄芩素在胃和小肠中吸收良好,在结肠有少量吸收。黄芩素在各部位的吸收程度明显优于黄芩苷,提示黄芩素比黄芩苷更适于制成口服吸收制剂;黄芩素具有广泛的吸收窗,提示适宜制成缓控释制剂。

Objective： To study the absorption kinetics of baicalin and baicalein in rats＇ stomachs and intestines. Method： The drug concentration by in situ perfusion in rats were determined by HPLC. Result： The hourly absorption percentages of baicalin in stomach, small intestine and colon were 8.05%, - 0.94% and 2.32%, respectively, and baioalein with 34.53 %, 30.61% and 4.89%, respectively. The absorption rate constants of baicalein were 0.090 7, 0.083 7, 0.076 6 and 0.048 3, respectively in duodenum, jejunum, ileum and colon. Conclusion： Baicalin is moderately absorbed in stomach and poorly in small intestine and colon; Baicalein is well absorbed in stomach and small intestine but worse in colon, suggesting that the former is more suitable to be administered orally. The extensive absorption segments of bacailein suggests that it can be processed into a sustained-release preparation.