紫草素在Caco-2细胞的摄取特性

目的:研究紫草素(SKN)在Caco-2细胞的摄取特性.方法:以Caco-2细胞单层模型研究紫草素的细胞摄取规律.采用高效液相色谱法测定细胞中SKN浓度,考察时间、pH、药物浓度及抑制剂对Caco-2细胞摄取SKN的影响.结果:SKN在Caco-2细胞中的摄取呈时间依赖性；SKN在0.2 ～3.2 mg·L-1内的摄取呈线性增加,符合被动扩散过程；pH 8.0条件下药物的细胞摄取量(0.350±0.004) mg·g-1显著低于pH 5.0(0.450±0.008) mg·g-1,P＜0.01]；加入维拉帕米,叠氮化钠及2,4-二硝基酚后,与对照组相比,SKN的细胞摄取量显著低,分别为(0.320±0.007),(0.340±0.003),(0.260±0.007) mg·g-1(P ＜0.01).结论:SKN的细胞摄取机制主要是被动转运；P-糖蛋白未参与SKN的转运过程.

Uptake of Shikonin in Caco-2 Cell Monolayer

Objective:To observe uptake process of shikonin (SKN) in Caco-2 cell. Method: The concentration of SKN in cells was detected by HPLC and the mechanism of SKN absorption in cells was explored by studying the influencing of time, pH,drug concentration and inhibitors on the uptake of SKN in cells. Result: SKN in Caco-2 cells uptake was time-dependent; SKN at 0.2-3.2 mg·L^-1 concentration range of uptake increased linearly, which was consistent with passive diffusion process. The drug intake amount(0.350±0.004)mg·g^-1 under pH 8.0 was significantly lower than pH 5.0 (0.450±0.008)mg·g^-1, (P<0.01). Compared with the control group, SKN cell uptake was significantly higher after addition of verapamil(0.320±0.007)mg·g^-1,P<0.01], sodium azide (0.340±0.003)mg·g^-1,P<0.05]and 2, 4-dinitrophenol(0.260±0.007)mg·g^-1,P<0.01]. Conclusion: The mechanism of SKN absorption in cells mainly is passive transport and P-glycoproteins does not participate in the conveying process of SKN in Caco-2 cells.