The actions of amphetamine on neurotransmitters: a brief review.

The central stimulant actions of d-amphetamine are not altered in animals in which brain stores of catecholamines have been depleted with reserpine, but they are blocked by alpha-methyltyrosine, which inhibits catecholamine synthesis. The results of a variety of experiments suggest that the central actions of amphetamine result primarily from the ability of the drug to facilitate the release of newly synthesized dopamine from nerve terminals in the forebrain. The results of experiments in animals in which dopaminergic nerve terminals in various brain regions have been selectively destroyed by intracranial microinjection of 6-hydroxydopamine reveal that the locomotor stimulant actions of relatively low doses of amphetamine are dependent upon mesolimbic dopaminergic neurons, whereas the stereotyped behaviors induced by relatively larger doses of amphetamine are dependent upon nigrostriatal dopaminergic neurons. The central actions of amphetamine appear to be the primary result of interactions with dopamine neurons, but secondarily the drug also alters the dynamics of other putative neurotransmitters (e.g. acetylcholine, 5-hydroxytryptamine) in the brain.