This novel compound is an orally bioavailable antagonist of P2X3 P2X2 3 receptors, exhibiting potent activity with a pIC50 of 8 in both human and rat, and a pIC50 of 7.3 specifically for the human P2X2 3 receptor. It demonstrates high brain penetration, evidenced by a brain to plasma ratio of 6, and effectively blocks agonist-evoked intracellular Ca2+ flux and inward currents within the nanomolar range (10 nM to 1 µM) in cell lines that express human P2X3 and P2X2 3 receptors recombinantly. The compound also shows favorable pharmacokinetic properties, with a half-life (t1 2) of 1.63 hours and a time to reach maximum concentration (Tmax) of 30 minutes.
α,β-Methylene ATP dilithium, a phosphonic analog of ATP, serves as a ligand for P2X3 and P2X7 receptors. It is a potent agonist specifically targeting P2X1 and P2X3 receptors while exerting negligible activity on P2X2, P2X4, P2X5, P2X6, and P2X7 receptors.
Mambalgin 1 TFA, a selective inhibitor of ASIC1a (with IC50 values of 192 nM for human ASIC1a and 72 nM for the ASIC1a 1b dimer), preferentially binds to the channel in its closed inactive state. It demonstrates selectivity for ASIC1a over a range of other channels, including ASIC2a, ASIC3, TRPV1, P2X2, 5-HT3, Nav1.8, Cav3.2, and Kv1.2. In vivo, Mambalgin 1 TFA effectively prolongs the latency of the withdrawal response in mouse tail-flick and paw-flick tests.