Click here to close Hello! We notice that you are using Internet Explorer, which is not supported by Xenbase and may cause the site to display incorrectly. We suggest using a current version of Chrome, FireFox, or Safari.
XB-ART-18940
Br J Pharmacol 1995 Dec 01;1167:3021-7.
Show Gene links Show Anatomy links

Stereoselective uptake of beta-lactam antibiotics by the intestinal peptide transporter.

Wenzel U , Thwaites DT , Daniel H .


???displayArticle.abstract???
1. The stereoselective transport of beta-lactam antibiotics has been investigated in the human intestinal epithelial cell line, Caco-2, by use of D- and L-enantiomers of cephalexin and loracarbef as substrates. 2. The L-isomers of cephalexin, loracarbef and dipeptides displayed a higher affinity for the oligopeptide/H(+)-symporter in Caco-2 cells than the D-isomers. This was demonstrated by inhibition of the influx of the beta-lactam, [3H]-cefadroxil. 3. By measurement of the substrate-induced intracellular acidification in Caco-2 cells loaded with the pH-sensitive fluorescent dye BCECF (2',7'-bis(2-carboxyethyl)-5-(6)-carboxy-fluorescein), it was demonstrated for the first time that L-isomers of beta-lactams not only bind to the peptide transporter with high affinity but are indeed transported. 4. Efficient proton-coupled transport of L-beta-lactam antibiotics was also shown to occur in Xenopus laevis oocytes expressing the cloned peptide transporter PepT1 from rabbit small intestine. 5. Both cell systems therefore express a stereoselective transport pathway for beta-lactam antibiotics with very similar characteristics and may prove useful for screening rapidly the oral availability of peptide-derived drugs.

???displayArticle.pubmedLink??? 8680738
???displayArticle.pmcLink??? PMC1909205

???displayArticle.grants??? [+]

Species referenced: Xenopus laevis
Genes referenced: slc15a1

References [+] :
Artursson, Epithelial transport of drugs in cell culture. I: A model for studying the passive diffusion of drugs over intestinal absorptive (Caco-2) cells. 1990, Pubmed