Ramatroban_product_DataBase

Bioactivity

Ramatroban is a selective thromboxane A2 (TxA2, IC50=14 nM) antagonist, which also antagonizes CRTH2 (IC50=113 nM) by inhibiting PGD2 binding.

Invitro

Ramatroban is a potent human thromboxane receptor (hTP) antagonist with an IC50 of 18 nM in a human TP binding assay. Ramatroban inhibits prostaglandin D2 receptor DP2 (CRTH2) with an IC50 of 113 nM in a human DP2 binding assay. Ramatroban also inhibits human CYP isoform CYP2C9 with an IC50 of 15 μM[1]. Ramatroban is a selective thromboxane-type prostanoid (TP) receptor antagonist. PGD2-stimulated human eosinophil migration is shown to be mediated exclusively through activation of CRTH2, and surprisingly, these effects are completely inhibited by Ramatroban. Ramatroban is an antagonist for CRTH2, and inhibits PGD2-induced migration of eosinophils via CRTH2 blockade. 3H-labeled PGD2 binds to a single site on CRTH2 transfectants with high affinity (KD=6.3 nM, Bmax=450 pM). Nonlabeled PGD2 inhibits the binding of 3H-labeled PGD2 to CRTH2 transfectants in a concentration-dependent manner with an EC50 value of 2.7 nM. Ramatroban shows significant inhibitory effects on the binding of 3H-labeled PGD2 to CRTH2, albeit with much lower potency (IC50=100 nM). Ramatroban also inhibits PGD2-induced Ca2+ mobilization in CRTH2 transfectants to almost the same extent with an IC50 value of 30 nM. Ramatroban completely inhibits the PGD2-induced migration of eosinophils in a concentration-dependent manner with an IC50 value of 170 nM[2].

In Vivo

Ramatroban is an orally bioavailable small molecule antagonist of CRTH2. Systemic administration of Ramatroban (30 mg/kg) in CRTH2+/+ mice produces the same effects as seen in CRTH2 deficiency. Ramatroban completely blocks LPS-induced decreases in social and object exploratory behavior (p<0.01). In addition, tumor-impaired social interaction and object exploratory behavior in CRTH2+/+ mice are completely reversed by a single injection of Ramatroban, even when the tumor is enlarged[3].

Name

Ramatroban

CAS

116649-85-5

Formula

C21H21FN2O4S

Molar Mass

416.47

Appearance

Solid

Transport

Room temperature in continental US; may vary elsewhere.

Storage

Powder	-20°C	3 years
	4°C	2 years
In solvent	-80°C	6 months
	-20°C	1 month

Reference

[1]. Stearns BA, et al. Novel tricyclic antagonists of the prostaglandin D2 receptor DP2 with efficacy in a murine modelof allergic rhinitis. Bioorg Med Chem Lett. 2009 Aug 15;19(16):4647-51. [2]. Sugimoto H, et al. An orally bioavailable small molecule antagonist of CRTH2, ramatroban (BAY u3405), inhibits prostaglandin D2-induced eosinophil migration in vitro. J Pharmacol Exp Ther. 2003 Apr;305(1):347-52. [3]. Haba R, et al. Central CRTH2, a second prostaglandin D2 receptor, mediates emotional impairment in the lipopolysaccharide and tumor-induced sickness behavior model. J Neurosci. 2014 Feb 12;34(7):2514-23.

PeptideDB

Ramatroban

CAS: 116649-85-5 F: C21H21FN2O4S W: 416.47