ABT-724 (trihydrochloride)

ABT-724 trihydrochloride is a potent and highly selective dopamine D₄ receptor agonist with an EC₅₀ of 12.4 nM for human dopamine D₄ receptor. ABT-724 trihydrochloride is a potent partial agonist at the rat D₄ (EC₅₀ of 14.3 nM) and the ferret D₄ receptor (EC₅₀ of 23.2 nM), and has no effect on dopamine D₁, D₂, D₃, or D₅ receptors. ABT-724 trihydrochloride could be useful for the treatment of erectile dysfunction and has favorable side-effect profile^[1]. IC50 & Target: EC50: 12.4 nM (Human dopamine D₄ receptor), 14.3 nM (Rat dopamine D₄ receptor) and 23.2 nM (Ferret dopamine D₄ receptor)^[1] In Vitro: ABT-724 exhibits a selective biochemical profile, as indicates by a lack of binding affinity for >70 neurotransmitter/uptake/ion channels including D₂, D₃, or D₅ receptors up to a 10 μM concentration. A weak affinity to 5-HT_1A receptors (K_i = 2780 nM) is observed. ABT-724 does not inhibit the PDE activity of PDE1, PDE5, or PDE6 at 10 μM concentrations^[1]. In Vivo: ABT-724 (8.8 μg/kg; subcutaneous injection; daily; for 5 days; male adult Wistar rats) treatment dose-dependently facilitates penile erection when given s.c. to conscious rats^[1].