Neurochemical changes in rat striatum and substantia nigra following drug administration : Evidence for an amino acid-dopamine-acetylcholine link.

The effects of a number of drugs that deplete catecholamines or block their receptors were investigated on the levels of free amino acids and glutamate decarboxylase activity in rat striatum and substantia nigra, in an attempt to clarify the possible links between catecholamine and amino acid transmitter function. While none of the drugs tested were significantly active in the striatum, profound changes occurred in the substantia nigra. The data are discussed in relation to the possible mechanisms involved.