Blockade of both pilocarpine and amphetamine-induced head-shaking with dopamine receptor antagonists.
The range of central dopaminergic mechanisms involved in both d-amphetamine- and pilocarpine-induced head-shaking was studied in 7--9 days old rats by means of two DA antagonists: pimozide and spiroperidol. Both blocking agents exert their effects on H--S following dose-response curves which are similar, whatever the drug used to evoke head-shaking. A complete blocking effect on H--S is reached with pimozide at a dose of 2 mg kg-1; with spiroperidol at 0.1 mg kg-1 (for pilocarpine-induced H--S) and at 0.2 mg kg-1 (for H--S evoked by d-amphetamine). These results, together with those previously reported, suggest that dopaminergic and cholinergic facilitatory influences on H--S seem to be organized in series.
D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D003913:Dextroamphetamine / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D010862:Pilocarpine / Q000037:antagonists & inhibitors* / Q000494:pharmacology; D010868:Pimozide / Q000494:pharmacology; D051381:Rats; D011954:Receptors, Dopamine / Q000187:drug effects*; D013134:Spiperone / Q000494:pharmacology
D011954:Receptors, Dopamine; D010862:Pilocarpine; D010868:Pimozide; D013134:Spiperone; D003913:Dextroamphetamine