The effects of neuroleptics with central dopamine and noradrenaline receptor blocking properties in the L-DOPA and (+)-amphetamine-induced waking EEG in the rat.
1 A study was carried out in rats (prepared for chronic sleep recording) of the effects of pretreatment with neuroleptics differing in their relative antinoradrenaline and antidopamine receptor potencies, on the L-DOPA and (+)-amphetamine-induced increase in waking EEG. 2 Haloperidol (0.6 mg/kg), which blocks central dopamine and noradrenaline (NA) receptors, reversed the EEG desynchronizing actions of L-DOPA and (+)-amphetamine. 3 Low doses of pimozide (0.4 to 0.8 mg/kg) which block dopamine receptors exclusively, were not able to modify the pharmacologically induced disruption of the sleep-awake cycle. However, at 1 mg/kg, a dose which also produces blockade of NA receptors, pimozide counteracted the increase in waking elicited by (+)-amphetamine. 4 Spiroperidol (1 to 4 mg/kg) which is devoided of NA receptor blocking properties, failed to reverse the L-DOPA or (+)-amphetamine-induced arousal. 5 Our results suggest that the increased waking time observed after the catecholamine agonists is related to an increased availability of NA rather than dopamine.
D000818:Animals; D014150:Antipsychotic Agents / Q000494:pharmacology*; D003913:Dextroamphetamine / Q000494:pharmacology*; D004569:Electroencephalography; D006220:Haloperidol / Q000494:pharmacology; D007980:Levodopa / Q000494:pharmacology*; D008297:Male; D009638:Norepinephrine / Q000502:physiology; D010868:Pimozide / Q000494:pharmacology; D051381:Rats; D011941:Receptors, Adrenergic / Q000187:drug effects*; D011954:Receptors, Dopamine / Q000187:drug effects*; D012890:Sleep / Q000187:drug effects; D013134:Spiperone / Q000494:pharmacology; D014851:Wakefulness / Q000187:drug effects
D014150:Antipsychotic Agents; D011941:Receptors, Adrenergic; D011954:Receptors, Dopamine; D010868:Pimozide; D007980:Levodopa; D013134:Spiperone; D006220:Haloperidol; D003913:Dextroamphetamine; D009638:Norepinephrine