Transport of glutathione prostaglandin A conjugates by the multidrug resistance protein 1.
FEBS Lett
; 419(1): 112-6, 1997 Dec 08.
Article
en En
| MEDLINE
| ID: mdl-9426231
The human multidrug resistance protein MRP1 mediates transport of organic substrates conjugated to glutathione, glucuronide, or sulfate. The naturally occurring prostaglandins A1 and A2 can form two diastereomeric glutathione S-conjugates, and it has been speculated that these might be substrates for MRP1. Here we present evidence that polarized MDCKII cells expressing MRP1 cDNA transport PGA1-GS to the basolateral side of a cell monolayer, in accordance with the lateral localization of human MRP1 in these cells. Furthermore, we show that vesicles made from yeast cells expressing MRP1 cDNA and from mouse erythrocytes (known to contain mrpl) actively accumulate both diastereomers of PGA2-GS with a similar efficiency. Recently, we generated mice with a homozygous mutant mrp1 allele. Uptake of PGA2-GS in vesicles made from erythrocytes of these mice was 3.2 times lower than in wild-type vesicles, but was still significantly above background. This residual transport activity was partly inhibited by methotrexate and cAMP, whereas mrp1-mediated activity was unaffected by these compounds. We conclude that mouse erythrocytes contain at least two transport systems for PGA2-GS. One of these is mrp1; the other one has not been identified yet, but can be inhibited by methotrexate and cAMP.
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Colección:
01-internacional
Base de datos:
MEDLINE
Asunto principal:
Miembro 1 de la Subfamilia B de Casetes de Unión a ATP
/
Glutatión
Límite:
Animals
/
Humans
Idioma:
En
Revista:
FEBS Lett
Año:
1997
Tipo del documento:
Article
Pais de publicación:
Reino Unido