The compound 6-aminodopamine is a powerful CNS catecholaminergic neurotoxin. Small dosages of 6-aminodopamine injected intraventricularly markedly depress electrical self-stimulation rates in rats. This 6-aminodopamine treatment produced whole brain lowering of norepinephrine to ca. 50% of normal while the dopamine content was unchanged. The possible use of 6-aminodopamine treatment to elucidate the relative roles of norepinephrine and dopamine pathways is discussed.