GBR 12909 is a potent inhibitor that blocks dopamine uptake (IC50 = 1-51 nM). It is more than 100-fold less effective at blocking serotonin or noradrenaline uptake. GBR 12909 effectively inhibits dopamine uptake in vivo, leading to consequent stimulation of dopamine receptors. GBR 12909 also inhibits pyrilamine binding to the histamine H1 receptor (IC50 = 18 nM) but poorly inhibits ligand binding to dopamine, adrenergic, acetylcholine, serotonin, and γ-aminobutyric acid receptors. It also blocks ligand binding to sigma receptors in rat brain (IC50 = 48 nM).
