大鼠肠管外翻模型对人参皂苷Rg1 吸收机制的研究

目的 建立准确、灵敏、可靠的Rg1 HPLC MS测定方法, 研究Rg1 是否存在分肠段吸收的差异并考察小肠上皮组织上的P-糖蛋白(P-glycoprotein) 对人参皂苷Rg1 吸收的影响。 方法 在不同肠段(回肠和空肠) 的肠管外翻模型中加入20 μg·ml-1 Rg1Krebs 液, 在不同时间点取样并测定囊内药物浓度,比较两个小肠段对Rg1 通透能力的差异, 同时观察P-糖蛋白抑制剂维拉帕米对Rg1 吸收的影响。 结果 不同肠段(回肠和空肠) 的体外模型试验结果表明, Rg1 在不同肠段的吸收良好, 且无明显差异。维拉帕米对Rg1 的吸收未见显著影响。 结论 Rg1 在大鼠的各个肠段的吸收无显著性差异, Rg1 可能不是P-糖蛋白的底物。

Study on absorption mechanism of ginsenoside Rg1 using rat everted gut sac

AIM: To develop an accurate, sensitive and reliable HPLC MS detection method for the ginsenoside Rg1, and to study the absorption characteristics of Rg1 in different intestinal sections (ileumand jejunum) and the influence of p-glycoprotein on the absorption rate. METHODS: Rat everted gut sac system was used. Sac containing drug free Krebs solution was immersed into the Krebs solution containing 20 mg·mL^-1 Rg1.The solution inside the sac was collected and drug concentration was determined by validated ESI-HPLC-MS method.Verapamil, a p-glycoprotein inhibitor, was used to study the influence of p-glycoprotein on the absorption of Rg1. RESULTS: The Rg1 concentration in the sac was increasing according to the time and there is no difference of the absorption rate between ileum and jejunum.Verapamil had no effect on the absorption of Rg1 in sac system. CONCLUSION: There is no difference for Rg1 absorption between ileum and jejunum of rat.Rg1 might not be the substrate of p-glycoprotein.