title: Photoaffinity labeling of the anionic sites in Caco-2 cells mediating saturable transport of hydrophilic cations ranitidine and famotidine.
abstract: The H(2) antagonists, ranitidine and famotidine, exhibit saturable absorptive transport across Caco-2 cell monolayers and human intestine via a yet unidentified mechanism. A photoreactive derivative of famotidine has been synthesized and evaluated as a photoaffinity probe for the putative transporter protein(s). The probe irreversibly inhibited ranitidine transport across Caco-2 cell monolayers and irreversibly increased the transepithelial electrical resistance (TEER) after UV activation. Photoaffinity labeling was protected by a molar excess of famotidine.
authors.affiliation: Division of Drug Delivery and Disposition, School of Pharmacy, The University of North Carolina at Chapel Hill, Chapel Hill, North Carolina 27599, USA.
authors.forename: David L
authors.initials: DL
authors.lastname: Bourdet
authors.forename: Kiho
authors.initials: K
authors.lastname: Lee
authors.forename: Dhiren R
authors.initials: DR
authors.lastname: Thakker
mesh_terms: D001692:Biological Transport; D018938:Caco-2 Cells; D002352:Carrier Proteins / Q000378:metabolism; D004553:Electric Conductivity; D015738:Famotidine / Q000031:analogs & derivatives* / Q000138:chemical synthesis* / Q000493:pharmacokinetics; D006635:Histamine H2 Antagonists / Q000138:chemical synthesis* / Q000493:pharmacokinetics; D006801:Humans; D019920:Photoaffinity Labels / Q000138:chemical synthesis* / Q000493:pharmacokinetics; D011899:Ranitidine / Q000031:analogs & derivatives* / Q000138:chemical synthesis* / Q000493:pharmacokinetics; D014466:Ultraviolet Rays
chemical_list: D002352:Carrier Proteins; D006635:Histamine H2 Antagonists; D019920:Photoaffinity Labels; D015738:Famotidine; D011899:Ranitidine