Brompheniramine (maleate)

Brompheniramine ((±)-Brompheniramine) maleate is a potent and orally active antihistamine of the alkylamine class. Brompheniramine maleate is a selective histamine H1 receptor antagonist with a K_d of 6.06 nM. Brompheniramine maleate can block the hERG channels, calcium channels, and sodium channels with IC₅₀s of 0.90 μM, 16.12 μM and 21.26 μM, respectively. Brompheniramine maleate has anticholinergic, antidepressant and anesthetic properties and can be used for allergic rhinitis research^[1][2][3][4]. In Vitro: Brompheniramine (0.1-100 μM) blocks hERG K⁺ channels expressed in CHO cells in a concentration-dependent manner with an IC₅₀ of 0.90±0.14 μM, and reduced peak tail current amplitude measured at -60 mV (cells are depolarized for 2 s to +20 mV from a holding potential of -80 mV followed by a 3s repolarization back to -60 mV)^[3].
Brompheniramine (1, 10 and 100 μM) significantly shortens the APD₅₀ and depresses the plateau phase on the action potential in guinea pig papillary muscle, as well as slightly prolongs the APD₉₀ in guinea pig papillary muscle at 10 and 100 μM^[3].
Brompheniramine (0.1-100 μM) inhibit the amplitude of the Ca²⁺ channel currents in rat ventricular myocytes by 14.1±1.1, 31.1±5.8, 38.0±3.8 and 90.2±3.7% at 0.1, 1, 10 and 100 μM, respectively^[3].
Brompheniramine blocks muscarinic cholinergic receptors in human chinese hamster ovary (CHO) cells^[4]. In Vivo: Brompheniramine (0.3-3 μM; SC, single dosage) induces cutaneous analgesia in rats^[1].