Electrocortical spectrum power effects of different classes of neuroleptics in rats

In freely moving rats the effects on behaviour and ECoG spectrum power of different classes of neuroleptics (phenothiazines, butyrophenones and benzamides) after systemic and intraventricular administration were studied. Chlorpromazine and haloperidol given systemically or microinjected into the third cerebral ventricle produced behavioural and ECoG slow-wave sleep (SWS) accompanied by a significant increase in ECoG total voltage power as well as in the lower frequency bands; haloperidol was found to be more powerful in inducing behavioural and SWS. In contrast, equimolar doses of 1-sulpiride given systemically or higher doses microinjected into the third cerebral ventricle did not produce significant behavioural and ECoG changes. Thus, the present experiments confirm that neuroleptic drugs may possess a different ECoG profile depending on their structure and provide further evidence concerning the role played by dopaminergic mechanisms in the control of sleep-arousal.