title: Active secretion of the fluoroquinolone ciprofloxacin by human intestinal epithelial Caco-2 cell layers.
abstract: 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.
authors: Gastrointestinal Drug Delivery Research Centre, Medical School, University of Newcastle upon Tyne.
authors: N M
authors: NM
authors: Griffiths
authors: B H
authors: BH
authors: Hirst
authors: N L
authors: NL
authors: Simmons
mesh_terms: D001386:Azides / Q000494:pharmacology; D002478:Cells, Cultured; D002939:Ciprofloxacin / Q000378:metabolism* / Q000493:pharmacokinetics; D003847:Deoxyglucose / Q000494:pharmacology; D004848:Epithelium / Q000187:drug effects / Q000378:metabolism; D006801:Humans; D007413:Intestinal Mucosa / Q000187:drug effects / Q000378:metabolism*
chemical_list: D001386:Azides; D002939:Ciprofloxacin; D003847:Deoxyglucose