An agonist of the dopamine D1 receptor (Ki=40 nM); induces activity equal to or greater than dopamine in fish retinas and rat caudate-putman (EC50s = 7.4 and 1.1 nM, respectively); does not show agonist behavior for the D2 receptor expressed in MMQ cells (≤10 μM); induces desensitization of dopamine-stimulated cAMP accumulation and reduces D1 receptor expression by 79% in C-6 glioma cells expressing monkey D1A receptors (10 μM); increases locomotor activity 5.3-fold and reduces disease severity in a MPTP-treated marmoset model of Parkinson's disease (3 μmol/kg s.c.); elicits over a 230% increase in cortical and hippocampal acetylcholine release (4 μmol/kg, s.c.)