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目的:采用MDCK细胞单层模型考察安石榴苷跨膜转运特性.方法:CCK8法筛选安石榴苷对MDCK细胞作用的安全浓度,Millicell-ERS测量细胞单层的TEER值确定细胞单层的完整性及致密性,考察给药浓度、方向、时间、温度、维拉帕米和ED-TA-Na2不同条件下安石榴苷的转运情况,采用HPLC法测定安石榴苷浓度,并计算表观渗透系数(Papp)和外排率(ER).结果:安石榴苷在MDCK模型上累积转运量具有时间和浓度依赖性,在100～300μg·ml-1浓度范围内测得的顶侧(AP)到基底侧(BL)的Papp值为(6.13±0.12)×10-7 cm·s-1、(6.96±0.26)×10-7 cm·s-1、(5.94±01.0)×10-7 cm·s-1,未随浓度升高而增大,4℃时转运量降低,P-gp抑制药维拉帕米可以促进APB-L方向的转运,加入EDTA-Na2后Papp(AP-BL)显著增大.结论:安石榴苷以被动转运为主兼有主动转运参与,是P-糖蛋白(P-gp)的底物受到P-gp的外排作用,同时有细胞旁路转运途径.“,”Objective:To investigate the transport mechanism of punicalagin in MDCK monolayer model .Methods:The safe con-centration of punicalagin in MDCK cells was determined by CCK8 assay.Millicell -ERS was used to measure cell monolayer TEER value to determine the integrity of the cell monolayer .The effects of direction , drug concentration , time, P-gp inhibitor and EDTA-Na2 on the absorption and transport of punicalagin were studied systematically .And then the drug concentration was analyzed by HPLC to calculate the apparent permeability coefficient (Papp) and efflux ratio(ER).Results: Punicalagin transport in MDCK cells was time and concentration dependent .Punicalagin showed poor absorption in MDCK cells .Papp from apical to basolateral side ( AP-BL) within the concentration range of 100-300μg· ml-1 was (6.13 ±0.12) ×10 -7 cm· s-1 , (6.96 ±0.26) ×10 -7 cm· s-1 and (5.94 ±0.10) ×10 -7 cm· s-1 , respectively .P-gp inhibitor and EDTA-Na2 could significantly increase the transport of punicalagin in AP-BL direc-tion, while the transport decreased at 4℃.Conclusion:The transport mechanism of punicalagin might be passive diffusion as the dom-inating process involving active transportation .Punicalagin is one of P-gp substrates with exocytosis and absorbed via the paracellular route.