LTE₄ Antagonist

MK-571 (L-660711) is an orally active, potent and selective competitive leukotriene D₄ (LTD₄) receptor antagonist, with K_i values of 0.22 and 2.1 nM in guinea pig and human lung membranes, respectively. MK-571 is also a MRP4 and ABCC1 (MRP1) inhibitor. MK-571 inhibits constitutive and antigen-stimulated S1P (sphingosine-1-phosphate) release.

MK-571 (L-660711) sodium is an orally active, potent and selective competitive leukotriene D₄ (LTD₄) receptor antagonist, with K_i values of 0.22 and 2.1 nM in guinea pig and human lung membranes, respectively. MK-571 sodium is also a inhibitor of multidrug resistance-associated protein MRP4 (ABCC4) and ABCC1 (MRP1). MK-571 sodium inhibits constitutive and antigen-stimulated S1P (sphingosine-1-phosphate) release.

Pranlukast is a highly potent, selective and competitive antagonist of peptide leukotrienes. Pranlukast inhibits [³H]LTE₄, [³H]LTD₄, and [³H]LTC₄ bindings to lung membranes with K_is of 0.63±0.11, 0.99±0.19, and 5640±680 nM, respectively.

Tipelukast (KCA 757) is a sulfidopeptide leukotriene receptor antagonist, an orally bioavailable anti-inflammatory agent and used for the treatment of asthma.

Pranlukast hemihydrate is a highly potent, selective and competitive antagonist of peptide leukotrienes. Pranlukast inhibits [³H]LTE₄, [³H]LTD₄, and [³H]LTC₄ bindings to lung membranes with K_is of 0.63±0.11, 0.99±0.19, and 5640±680 nM, respectively.

AS-35 is an orally effective, potent and selective antagonist of leukotrienes, antagonizes LTC4-, LTD4 and LTE4-induced contractions of the ileum with IC₅₀ values of 8 nM, 4 nM and 3 nM, respectively, and has antiallergic activities.

MDL 43291 is a competitive leukotriene (LT) receptor antagonist. MDL 43291 antagonize LTD4 and LTE4 with pA2 of 6.7. MDL 43291 does not antagonize histamine, carbachol or substance P. MDL 43291 can be used for the researches of inflammation and immunology, such as asthma.