Background:

Umeclidinium bromide is a potent and long-acting antagonist of muscarinic cholinergic receptor (mAChR) with Ki values of 0.16nM, 0.15nM, 0.06nM, 0.05nM and 0.13nM for M1, M2, M3, M4 and M5, respectively [1].

Umeclidinium bromide is developed for the treatment of chronic obstructive pulmonary disease (COPD). It can help patients of COPD achieve sufficient oxygenation of extrapulmonary tissues through dilating the airways. In the in vitro assay, umeclidinium binds to recombinant human mAChRs with Ki value of 0.16nM, 0.15nM, 0.06nM, 0.05nM and 0.13nM for M1-M5, respectively. Umeclidinium is selective against mAChR over other unrelated receptors or channels such as κ and σ opiod receptors, Na+ channel and dopamine transporter. In CHO cells transfected with human recombinant mAChRs, umeclidinium affects the calcium flux responsed to Ach with pA2 values of 9.6-10.6 for M1-M3. In a murine model, administration of umeclidinium can reverse the bronchoconstriction caused by Ach [1].

参考文献:
[1] Salmon M, Luttmann M A, Foley J J, et al. Pharmacological characterization of GSK573719 (umeclidinium): a novel, long-acting, inhaled antagonist of the muscarinic cholinergic receptors for treatment of pulmonary diseases. Journal of Pharmacology and Experimental Therapeutics, 2013, 345(2): 260-270.