Characterization of dopamine receptors involved in apomorphine-induced pecking in pigeons.
1. The possible involvement of subtypes of dopamine-receptors in apomorphine induced pecking was studied in pigeons. Different doses of apomorphine induced pecking in pigeons which was dose-dependent. 2. The response was decreased by SCH 23390 (D-1 antagonist) or high doses of sulpiride (D-2 antagonist) pretreatment, but increased by lower doses of sulpiride. 3. Combination of SCH 23390 with sulpiride completely antagonized the apomorphine effect. 4. Single dose administration of SKF 38393 (D-1 agonist) or bromocriptine (D-2 agonist) and combination of these drugs did not induce pecking, although either SK 23390 or bromocriptine increased the apomorphine-induced pecking which was decreased by SCH 23390 or sulpiride pretreatment. 5. It may be concluded that pecking, induced by apomorphine in pigeons, is elicited through activation of both D-1 and D-2 dopamine-receptors.
Zarrindast
M R
MR
Department of Pharmacology, Medical Faculty, University of Tehran, Iran.
Hajian-Heydari
A
A
Hoseini-Nia
T
T
D000818:Animals; D001058:Apomorphine / Q000037:antagonists & inhibitors / Q000494:pharmacology*; D010856:Columbidae; D003216:Conditioning, Operant / Q000187:drug effects*; D018492:Dopamine Antagonists; D004305:Dose-Response Relationship, Drug; D005260:Female; D008297:Male; D011954:Receptors, Dopamine / Q000187:drug effects / Q000502:physiology; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2
D018492:Dopamine Antagonists; D011954:Receptors, Dopamine; D017447:Receptors, Dopamine D1; D017448:Receptors, Dopamine D2; D001058:Apomorphine