Effects of Substantia Nigra Lesions on the Locomotor and Stereotypy Responses to Amphetamine

IT is usually supposed that amphetamine produces behavioural effects which include an increase of spontaneous motor activity and the elicitation of stereotyped behaviours¹, by causing a release of endogenous catecholamines in the central nervous system². This view is, for example, supported by the observation that amphetamine can release the catecholamines noradrenaline (NA) and dopamine (DA) from the central nervous system in vitro² and in vivo^{3, 4} and that inhibition of catecholamine biosynthesis blocks the amphetamine effect⁵. Anatomical studies of the distribution of neurones containing catecholamine however, raise, questions about the general applicability of this hypothesis⁶.