利福平对地高辛小肠吸收作用的影响

为探讨合并应用利福平时地高辛小肠吸收的持征,特建立药物透膜吸收的离体、在体动物实验模型,采用外翻小肠囊法收集透膜液样本,静脉及肠道给药后采集血浆样本.用125I标记试剂盒免疫分析法测试透膜液和血浆中地高辛浓度,TopFit药动学软件求算药代动力学参数.结果表明,合用利福平后,地高辛小肠透膜量大幅度增加,血浆地高辛浓度升高,清除率下降.利福平对地高辛的肠道吸收产生了明显的增强作用,推测这种相互作用与小肠P-gp药泵作用受到抑制有关.

The Effect of Rifampin on the Intestine Digoxin Absorption

To explore absorption features of digoxin in small intestine by co administration of rifampin, an in vitro permeation model using the everted sacs method and an in situ absorption model using intestine administration or intravenous injection method were established, respectively. The sample and plasma concentrations of digoxin were measured by a digoxin RIA kit with 125 I labeled antigen. The data were fitted by TopFit pharmacokinetic program. The results showed that after co administration of rifampin the intestine permeation amount of digoxin and plasma digoxin concentration were increased significantly, total clearance decreased. The above findings revealed that absorption effect of digoxin in small intestine was enhanced by co administration of rifampin. It was suggested that inhibited P gp pump function might contribute to the interaction in the intestinal drug absorption.