The effect of acute lithium and rubidium pretreatment on apomorphine-induced pecking in pigeons.
The effects of different doses of lithium (5-320 mg/kg intramuscularly) and rubidium (0.25 32 mg/kg intramuscularly) on apomorphine-induced pecking were investigated in pigeons. These two cations did not induce pecking by itself. Intramuscular administration of apomorphine (a mixed D1/D2 dopamine receptors agonist, 0.1-1.6 mg/kg) induced pecking in a dose-dependent manner. SCH 23390 (D1 dopamine receptor antagonist, 0.02-0.08 mg/kg) and sulpiride (D2 dopamine receptor antagonist, 25-100 mg/kg) decreased apomorphine-induced pecking dose-dependently. Combination of SCH 23390 (0.04 mg/kg) with sulpiride (50 mg/kg) caused a stronger inhibitory effect on apomorphine response. This indicates that both D1 and D2 dopamine receptors are involved in apomorphine-induced pecking. The response induced by apomorphine (0.2-0.8 mg/kg) was decreased in animals pretreated with lithium and rubidium. In these conditions, SCH 23390 and sulpiride produced a larger inhibitory effect on the apomorphine response, suggesting that acute lithium and rubidium pretreatment inhibit pecking by interfering with dopaminergic mechanisms.
Dehpour
A R
AR
Department of Pharmacology, School of Medicine, Tehran University of Medical Sciences, Iran.
Samini
M
M
Aliebrahimi
F
F
Chavoushzadeh
M A
MA
D000818:Animals; D001058:Apomorphine / Q000494:pharmacology*; D002712:Chlorides / Q000494:pharmacology*; D010856:Columbidae; D018491:Dopamine Agonists / Q000494:pharmacology*; D018021:Lithium Chloride / Q000494:pharmacology*; D012413:Rubidium / Q000494:pharmacology*; D013239:Stereotyped Behavior / Q000187:drug effects*
D002712:Chlorides; D018491:Dopamine Agonists; D018021:Lithium Chloride; D012413:Rubidium; D001058:Apomorphine; C032710:rubidium chloride