Influence of phenoxybenzamine on the stereotyped behaviour induced by fencamfamine in rats: evidence for a qualitative alteration.

The interactions between norepinephrine (NE) and dopamine (DA) systems in mediating stereotyped behaviour induced by different doses of fencamfamine (1-30 mg/kg) were studied in male rats. Pretreatment with phenoxybenzamine (5.0 mg/kg) resulted in a significant leftward shift of the control curve for stereotypy. The qualitative analysis of the stereotyped behaviour parameters when compared to controls showed: higher rearing frequency at a dose of 3.0 mg/kg; lower locomotor activity at a dose of 6.0 mg/kg; higher licking and gnawing frequencies at a dose of 10.0 mg/kg. These findings indicate that the role of DA systems on the stereotyped behaviour induced by fencamfamine is dependent on the degree of NE transmission in the CNS.