On the mechanism of central stimulation action of fencamfamine

The stereotypy induced by fencamfamine (10 mg/kg i.p.) was compared in different groups of rats which had been pretreated with catecholaminergic drugs. Pretreatment with alpha-methyl-p-tyrosine (alpha-MpT) did not abolish the stereotypy, however the combination of alpha-MpT plus reserpine decreased, while reserpine alone increased this response. Pretreatment with haloperidol or metoclopramide reduced the intensity of stereotyped behaviour induced by fencamfamine, while phenoxybenzamine increased this behaviour. Fencamfamine showed low affinity for binding sites of [3H]haloperidol and [3H]dihydroergocriptine. These results support the view that fencamfamine is an indirectly acting drug of the non-amphetamine class, which releases both norepinephrine (NE) and dopamine (DA) from presynaptic terminals leading to stereotyped behaviour.