Amphetamine-induced enhancement of ethanol consumption: role of central catecholamines.

Rats administered continuous low levels of amphetamine increase their free choice consumption of a 10% ethanol solution. The present experiment sought to determine the roles of central catecholamines in producing this effect by comparing the changes of ethanol consumption in rats implanted with control pellets or amphetamine pellets following intracerebral injections of 2 X 250 micrograms of 6-hydroxydopamine (6-OHDA), 6-OHDA preceded by 25 mg/kg of desipramine (to protect noradrenergic neurons from damage), or vehicle. The increase of ethanol consumption associated with continuous amphetamine administration was prevented by intracerebral 6-OHDA administration, but not by intracerebral 6-OHDA preceded by desipramine. There were no significant changes of ethanol consumption in animals receiving either 6-OHDA regimen followed by control pellet implantation. These data indicate that the increased consumption of ethanol obtained with continuous amphetamine administration is mediated by central noradrenergic systems.