Effect of Lesions of the Brain Noradrenergic Systems on Amphetamine-induced Hyperthermia and Locomotor Stimulation

Amphetamine-induced hyperthermia and increase of locomotor activity were studied in Wistar rats with bilateral electrolytic lesions of the locus coeruleus (LC) and ventral noradrenergic bundle (VB). The hyperthermic effect of 5 mg/kg i.p. of d,l-amphetamine was reduced by VB lesion but not by lesion involving selectively the LC. Both lesions significantly reduced the stimulatory action of amphetamine on the locomotor activity. These data indicate that both LC and VB are involved in amphetamine-induced locomotor stimulation. On the other hand, amphetamine hyperthermia can be dissociated from the effects on locomotion as regards the involvement of the brain noradrenergic systems.