ltd4 antagonist 1

LTD4 antagonist 1 is a potent and orally active antagonist of leukotriene D4 (LTD4; Ki: 0.57 nM).

Rupatadine (UR-12592) is a potent dual PAF H1 antagonist with Ki of 0.55 0.1 uM(rabbit platelet membranes guinea pig cerebellum membranes).IC50 value:Target: PAF H1 antagonistin vitro: Rupatadine competitively inhibited histamine-induced guinea pig ileum contraction (pA2 = 9.29 + - 0.06) without affecting contraction induced by ACh, serotonin or leukotriene D4 (LTD4). It also competitively inhibited PAF-induced platelet aggregation in washed rabbit platelets (WRP) (pA2 = 6.68 + - 0.08) and in human platelet-rich plasma (HPRP) (IC50 = 0.68 microM), while not affecting ADP- or arachidonic acid-induced platelet aggregation [1]. The IC50 for rupatadine in A23187, concanavalin A and anti-IgE induced histamine release was 0.7+ -0.4 microM, 3.2+ -0.7 microM and 1.5+ -0.4 microM, respectively whereas for loratadine the IC50 was 2.1+ -0.9 microM, 4.0+ -1.3 M and 1.7+ -0.5 microM. SR-27417A exhibited no inhibitory effect [2].in vivo: Rupatadine blocked histamine- and PAF-induced effects in vivo, such as hypotension in rats (ID50 = 1.4 and 0.44 mg kg i.v., respectively) and bronchoconstriction in guinea pigs (ID50 = 113 and 9.6 micrograms kg i.v.). Moreover, it potently inhibited PAF-induced mortality in mice (ID50 = 0.31 and 3.0 mg kg i.v. and p.o., respectively) and endotoxin-induced mortality in mice and rats (ID50 = 1.6 and 0.66 mg kg i.v.) [1]. rupatadine treatment improved the declined lung function and significantly decreased animal death. Moreover, rupatadine was able not only to attenuate silica-induced silicosis but also to produce a superior therapeutic efficacy compared to pirfenidone, histamine H1 antagonist loratadine, or PAF antagonist CV-3988 [3]. [1]. Merlos M, et al. Rupatadine, a new potent, orally active dual antagonist of histamine and platelet-activating factor (PAF). J Pharmacol Exp Ther. 1997 Jan;280(1):114-21. [2]. Queralt M, et al. In vitro inhibitory effect of rupatadine on histamine and TNF-alpha release from dispersed canine skin mast cells and the human mast cell line HMC-1. Inflamm Res. 2000 Jul;49(7):355-60. [3]. Lv XX, et al. Rupatadine protects against pulmonary fibrosis by attenuating PAF-mediated senescence in rodents. PLoS One. 2013 Jul 15;8(7):e68631.

LTD4 antagonist 2 (compound 6) 是一种 leukotriene D4 (LTD4) 拮抗剂，对半胱氨酸白三烯 1 受体 (CysLT1R) 的IC50为 2.8 μM。LTD4 antagonist 2 也是 G 蛋白偶联胆汁酸受体 1 (GPBAR1) 激动剂，可用于研究结肠炎、代谢综合征及其他与 GPBAR1 和 CysLT1R 相关的疾病。

Ritolukast (Wy-48252) 是一种口服活性的气溶胶白三烯 (LTD4 E4) 受体拮抗剂，可用于抑制气溶胶 LTD4 引起的豚鼠支气管收缩，ID50 为 0.5 mg kg。