Differential reversal by scopolamine and THIP of the antistereotypic and cataleptic effects of neuroleptics.

Scopolamine reversed the neuroleptic-induced catalepsy and neuroleptic blockade of amphetamine-induced stereotypies in rats. The effect on catalepsy was the most pronounced. Butyrophenones were mainly sensitive to scopolamine reversal whereas the thioxanthenes cis-Z-flupentixol and piflutixol were not significantly influenced. THIP did not change the effects of cis-Z-flupentixol, fluphenazine and haloperidol. The relevance of these findings for the use of stereotypy and catalepsy tests as screening for antiscizophrenic and extrapyramidal side-effects, respectively, is discussed.