[Amphetamine action on morphochemical brain organization].

The activity of enzymatic systems--monoamine oxidase, types A and B, and acetylcholinesterase involved in neuromediator utilisation and their levels correlation in the cortex and caudate nucleus brain tissue subfractions in control and during long (3 weeks) amphetamine (psychostimulator) injections in dosage 2.5 mg/kg were studied. Wistar and August rats different by behavioral characteristics were used. Differences of enzyme activity on subcellular level both in controls and in rats with dopaminergic dysfunction, caused by amphetamine, were found. Comparing to Wistar rats, in August ones characterized by lower motor activity and elevated stress sensitivity, amphetamine caused a significant MAO A and acetylcholinesterase activity inhibition, the changes being more pronounced in the caudate nucleus. It is suggested that the differences of enzymatic activity, reflecting the state of brain neuromediator metabolism and emerging in pathological conditions, may underlie a mechanism of CNS psasticity.