Possible storage of (+)-amphetamine in catecholaminergic terminals of the striatum and brainstem

6-Hydroxydopamine, given intraventricularly, did not affect the high concentrations of (+)-amphetamine present in the rat striatum and brainstem 1 h after its administration but considerably reduced the small amounts of (+)-amphetamine remaining after 5 h. In contrast, 5,6-dihydroxytryptamine did not modify the (+)-amphetamine concentrations at the times tested. These findings suggest that (+)-amphetamine might be stored in the catecholaminergic but not in the serotonergic central terminals.