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PredicateObject
rdf:type
lifeskim:mentions
pubmed:issue
3
pubmed:dateCreated
2001-8-15
pubmed:abstractText
The purpose of this work was to determine whether the in vitro bronchiolar epithelial cell model, Calu-3, possesses efflux pump activity by the multidrug resistance-associated protein-1 (MRP1). Reverse transcription-polymerase chain reaction demonstrated MRP1 gene expression in Calu-3 cells. Indirect fluorescence studies showed a basolateral membrane localization of MRP1 compared with P-glycoprotein (Pgp) that was found on the apical side of these cells. An increase in the rate of accumulation of the MRP1 substrate calcein was observed following treatment with the organic anion/MRP1 inhibitor indomethacin, the Pgp inhibitors cyclosporin A (CsA) and vinblastine, as well as conditions of energy depletion. Total calcein efflux was significantly decreased with the MRP1 inhibitors probenecid and indomethacin, while total efflux was unchanged following treatment with CsA. In the latter case, however, intracellular calcein levels postefflux were significantly greater. Probenecid and indomethacin increased calcein net secretion 2.4- and 3.5-fold, respectively. The efflux of etoposide, a known substrate for both Pgp and MRP1, was shown to be mainly Pgp-mediated by using the multidrug-resistant inhibitors quinidine (mixed Pgp/MRP1), CsA (Pgp), and MK571 (MRP1). Together, these data suggest that Calu-3 cells possess MRP1 functional activity that is subordinate to Pgp efflux. We present here kinetic analysis of calcein efflux from Calu-3 cells to support our findings.
pubmed:language
eng
pubmed:journal
pubmed:citationSubset
IM
pubmed:chemical
pubmed:status
MEDLINE
pubmed:month
Sep
pubmed:issn
0022-3565
pubmed:author
pubmed:issnType
Print
pubmed:volume
298
pubmed:owner
NLM
pubmed:authorsComplete
Y
pubmed:pagination
1199-205
pubmed:dateRevised
2006-11-15
pubmed:meshHeading
pubmed:year
2001
pubmed:articleTitle
Multidrug resistance-associated protein-1 functional activity in Calu-3 cells.
pubmed:affiliation
Department of Pharmaceutical Chemistry, The University of Kansas, Lawrence, Kansas 66047-3729, USA.
pubmed:publicationType
Journal Article, Research Support, Non-U.S. Gov't