Electroencephalographic characterization of brain dopaminergic stimulationby apomorphine in healthy volunteers

Apomorphine, a dopamine receptor agonist (given in a dose of 0.75 mg s.c.), was administered to 8 healthy volunteers; electroencephalograph (EEG) and event-related potential (ERP) mapping were performed before dosing and 0.5, 1.5 and 2.5 h after dosing. Apomorphine caused an overall increase in beta activity at time 0.5 h in both absolute and relative energy; P300 and CNV ERPs were not significantly altered, although a tendency towards increased P300 latency was seen. The results confirm that the EEG mapping technique i s sufficiently sensitive to monitor dopaminergic neurochemical stimulation by means of apomorphine. This could lead to a new, noninvasive and repeatab le method for monitoring central neuronal systems which is more convenient to apply repeatedly than for example positron emission tomography technique s. Furthermore, electrophysiological techniques undoubtedly constitute an a lternative to classical neuroendocrinological methods, allowing a more dire ct assessment of central nervous system neurotransmission. Finally, these E EG approaches could lead to better characterization of drugs acting on dopa minergic pathways, such as antipsychotics.