[Effect of L-DOPA on the function of the brain neuromediator systems].

L-DOPA effects on the activities of enzymes controlling the neurotransmitters utilization: monoamine oxidases (MAO) A and B and acetylcholinesterase (AChE) were demonstrated in synaptosomes and mitochondria of the cells in sensorimotor cortex and caudate nucleus. Sixty minutes after a single dose of L-DOPA the MAO and AChE activities were virtually unchanged in subfractions of both brain regions. After a prolonged (30 days) treatment (1000 mg/kg total dose) MAO B activity increased whereas the MAO B and AChE activities decreased only in cortical synaptosomes and mitochondria. The data suggest that under effect of L-DOPA a definite reciprocity arises in the neurotransmitter catabolic systems in a specific manner for each brain structure.