Griffiths N M, Hirst B H, Simmons N L
Gastrointestinal Drug Delivery Research Centre, Medical School, University of Newcastle upon Tyne.
Br J Pharmacol. 1993 Mar;108(3):575-6. doi: 10.1111/j.1476-5381.1993.tb12844.x.
The bidirectional transepithelial fluxes of ciprofloxacin, an antibacterial fluoroquinolone, across the human intestinal epithelial Caco-2 cell-line show marked asymmetry. Basal-to-apical flux of ciprofloxacin (10 microM) exceeds apical-to-basal flux indicating net secretion. Net ciprofloxacin secretion is abolished by azide/2-deoxy-D-glucose treatment, displays saturation kinetics (Km = 0.89 +/- 0.23 mM, Vmax 44.3 +/- 4.9 nmol cm-2.h) and competition by other fluoroquinolones. A specific, active secretion in Caco-2 epithelia may explain the transintestinal elimination of ciprofloxacin observed in pharmacokinetic studies in man.
抗菌氟喹诺酮类药物环丙沙星在人肠上皮Caco-2细胞系中的双向跨上皮通量显示出明显的不对称性。环丙沙星（10微摩尔）从基底侧向顶侧的通量超过从顶侧向基底侧的通量，表明存在净分泌。叠氮化物/2-脱氧-D-葡萄糖处理可消除环丙沙星的净分泌，呈现饱和动力学（Km = 0.89 ± 0.23毫摩尔，Vmax 44.3 ± 4.9纳摩尔·厘米-2·小时），并且会受到其他氟喹诺酮类药物的竞争。Caco-2上皮细胞中的特异性主动分泌可能解释了在人体药代动力学研究中观察到的环丙沙星经肠道消除的现象。
