Transport of fluorescein methotrexate by multidrug resistance-associated protein 3 in IEC-6 cells.

Article Details

Citation

Li T, Ito K, Horie T

Transport of fluorescein methotrexate by multidrug resistance-associated protein 3 in IEC-6 cells.

Am J Physiol Gastrointest Liver Physiol. 2003 Sep;285(3):G602-10.

PubMed ID
12909565 [ View in PubMed
]
Abstract

The transport characteristics of fluorescein methotrexate (F-MTX) were studied by using the rat intestinal crypt cell line IEC-6. Enhanced accumulation of F-MTX at 4 degrees C suggests the existence of an active efflux system. MK-571, an inhibitor of the multidrug resistance-associated protein/ATP binding cassette C (MRP/ABCC) family, also enhanced the accumulation of F-MTX. Transcellular transport of F-MTX from the apical to the basolateral compartment was 2.5 times higher than the opposite direction. This vectorial transport was also reduced by MK-571, indicating the presence of Mrp-type transporter(s) on the basolateral membrane. Mrp3 mRNA was readily detectable, and the protein was localized on the basolateral membrane. Uptake of FMTX into membrane vesicles from IEC-6 cells and Spodoptera frugiperda-9 cells expressing rat Mrp3 were both ATP dependent and saturable as a function of the F-MTX concentration. Similar Km values (11.0 +/- 1.8 and 4.5 +/- 1.1 microM) and inhibition profiles by MK-571, estradiol-17beta-d-glucuronide, and taurocholate for the ATP-dependent transport of F-MTX into these vesicles were obtained. These findings suggest that the efflux of F-MTX is mediated by Mrp3 on the basolateral membrane of IEC-6 cells.

DrugBank Data that Cites this Article

Drug Transporters
DrugTransporterKindOrganismPharmacological ActionActions
MethotrexateCanalicular multispecific organic anion transporter 2ProteinHumans
Unknown
Substrate
Inhibitor
Details
Taurocholic acidCanalicular multispecific organic anion transporter 2ProteinHumans
Unknown
Substrate
Inhibitor
Details