Pranlukast is an orally bioavailable cysteinyl leukotriene 1 (CysLT1) receptor antagonist (IC50s = 4.3-7.2 nM in radioligand binding assays).1 It is selective for the CysLT1 receptor over the CysLT2 receptor (IC50 = 3,620 nM for the human receptor).2 Pranlukast inhibits mucus secretion induced by leukotriene D4 (LTD4; Item No. 20310) in isolated guinea pig trachea with an IC50 value of 0.3 µM.3 It inhibits TNF-α-induced NF-ĸB p65 nuclear localization in U937 and Jurkat cells when used at concentrations of 10 and 100 µM.4 Pranlukast inhibits bronchoconstriction induced by LTC4 (Item No. 20210), LTD4, and LTE4 (Item No. 20410), but not LTB4 (Item No. 20110), in guinea pigs (ID50s = 0.8, 1, 0.7, and >500 µg/kg, respectively).5 It reduces cortical infarct volume by 81.6% and decreases neuronal death in the cortex, hippocampus, and striatum in a rat model of ischemia induced by middle cerebral artery occlusion (MCAO) when administered at a dose of 0.03 mg/kg.6WARNING This product is not for human or veterinary use.