Levocabastine

Levocabastine (R 50547) is a potent and selective histamine H1-receptor antagonist. Levocabastine hydrochloride is also a selective, high affinity neurotensin receptor subtype 2 (NTR2) antagonist, with a K_i of 17 nM for mNTR2. Levocabastine can act as a VLA-4 antagonist, interferes with conjunctival eosinophil infiltration in allergic conjunctivitis (AC)^[1][2][3]. In Vitro:Levocabastine (0-1000 μM; HEK-293 cells) causes inhibition of ¹²⁵I-FN binding to the SPA bead-associated α4β1 integrin in a concentration-dependent manner with an IC₅₀ of 406.2μm^[3].
Levocabastine (0-1000 μM; 30 min; Jurkat cells and EoL-1 cells) inhibits α4β1 integrin/VCAM-1-mediated cell adhesion in vitro. Levocabastine inhibits α4β1 integrindependent adhesion of Jurkat cells to VCAM-1 with an IC₅₀ of 395.6 μM, and the adhesion of EoL-1 cells with an IC₅₀ of 403.6 μM. Moreover, Levocabastine inhibits adhesion of human eosinophils to VCAM-1-coated wells (IC₅₀=443.7 μM)^[3]. In Vivo:Levocabastine (R 50547; 0.25 mg/kg; i.p.; twice a day for five days; guinea-pig with Parainfluenza-3 (PI-3) virus) inhibits the virus-induced airway hyperresponsiveness^[1].
Levocabastine (0.05 mg/kg; i.p.; once; male C57BL/6J mice) blocks anti-stress effect ofβ-LT on mouse behavior^[2].
Levocabastine (500 µg/eye; drops eye; once; ovalbumin-sensitized guinea pigs) induces allergic conjunctivitis (AC) and a significant increase of conjunctival VLA-4^[3].