BP 897

BP 897 is a potent and partial dopamine D3 receptor agonist and a weak D2 receptor antagonist. BP 897 displays a high affinity at the dopamine D3 receptor (K_i=0.92 nM) and a 70 times lower affinity at the D2 receptor (K_i=61 nM). BP 897 exhibits selective inhibition of cocaine-seeking behavior^[1]. In Vitro: BP 897 also displays low affinities at D1 and D4 receptors (K_i=3 and 0.3 μM, respectively), as well as at α1 and α2 adrenergic receptors (K_i=60 and 83 nM, respectively), 5HT1A and 5HT7 receptors (K_i=84 and 345 nM, respectively), and negligible affinities (K_i>1 μM) atmuscarinic, histamine and opiate receptors^[1].
In NG 108-15 cells expressing the human D3 receptor, BP 897 inhibits forskolin-induced cyclic AMP accumulation with an EC₅₀ of 1 nM. BP 897 activates mitogenesis and this response is antagonized by the preferential D3 receptor antagonist Nafadotride (1 μM). BP 897 also partially antagonized the response induced by quinpirole (10 nM)^[1]. In Vivo: BP 897 (0.05, 0.5, 1 mg/kg; i.p.; 30 min before the session) reduces cocaine-seeking behaviour before the first infusion of cocaine, in a dose-dependent manner, at doses similar to those at which BP 897 produced its responses on rotations and c-fos expression^[1].