Amoxapine in experimental psychopharmacology: a neuroleptic or an antidepressant?

2-Chloro-11-(piperazinyl)dibenz[b,f][1,4]-oxazepine (amoxapine) gives an unusual spectrum in psychopharmacological tests. Many of its effects are similar to those of neuroleptics: sedation, decrease in motor activity, catalepsy (which is, however, qualitatively different from that induced by classical neuroleptics), transitory suppression of avoidance reaction, antagonism of amphetamine induced toxicity in crowded mice and inhibition of stereotyped behavior induced by amphetamine in rats, and antagonism to various effects of apomorphine (stereotyped behaviour in rats, climbing behaviour, stereotyped behaviour and hypothermia in mice). At similar doses which produce the above mentioned effects, amoxapine also shows effects atypical for a neuroleptic, but which are relatively characteristic of antidepressants: antagonism of prochlorperazine-induced catalepsy in rats, inhibition of reserpine induced hypothermia in mice and enhancement of yohimbine toxicity in mice. The profile of this substance does not facilitate the anticipation of therapeutic effects in humans.