MK-571 sodium

MK-571 sodium (L-660711 sodium salt) is a selective, orally active antagonist of the CysLT1 receptor. MK-571 sodium is a multidrug resistance protein-2 (ABCC2, Mrp2) inhibitor used to demonstrate the role of Mrp2 in the cellular efflux of drugs, xenobiotics, and their conjugates. MK-571 sodium can inhibit the synthesis of K-4′-O-GlcA (19.7 μM) . MK571 dose-dependently inhibits the intracellular biosynthesis of all flavonol sulphates and glucuronides by Caco-2 cells. MK-571 sodium significantly inhibits phase-2 conjugation of kaempferol by cell-free extracts of Caco-2, and production of kaempferol-4′-O-glucuronide was competitively inhibited. In addition to inhibiting MRP2, MK571 is a potent inhibitor of enterocyte phase-2 conjugation.