The effects of scopolamine pretreatment on stereotyped behavior induced by apomorphine in rats withdrawn from long-term haloperidol administration.
1. The effects of scopolamine on intensity of stereotyped behavior induced by the ED50 dose of apomorphine in controls and in animals withdrawn from long-term haloperidol treatment were studied. 2. Doses of 1.0 and 3.0 microgram/kg of scopolamine increased apomorphine-induced stereotypy in both groups. However, this increase was smaller in the haloperidol-treated than in the control animals. 3. These data support the hypothesis that long-term administration of haloperidol may produce a change not only in dopaminergic but also in central cholinergic receptor sensitivity.
D000818:Animals; D001058:Apomorphine / Q000494:pharmacology*; D006220:Haloperidol / Q000008:administration & dosage*; D006801:Humans; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains; D011950:Receptors, Cholinergic / Q000187:drug effects; D012601:Scopolamine / Q000494:pharmacology*; D013239:Stereotyped Behavior / Q000187:drug effects*
D011950:Receptors, Cholinergic; D012601:Scopolamine; D006220:Haloperidol; D001058:Apomorphine