Effekten av Dopamin D-1 og D-2 receptor agonister på aber: Et adfærdsmæssigt korrelat til D-1 og D-2 receptor stimulation. Dopamin D-1 og D-2 agonister hos aber

Abstract

The effect of dopamine (DA) D-1 and D-2 receptor agonists was evaluated in five Cebus monkeys previously treated with haloperidol for two years. Three monkeys had developed oral tardive dyskinesia. The behavioural effects of the D-1 agonist SKF 38393, the D-2 agonist LY 171555 and apomorphine, a combined D-1/D-2 agonist, were investigated. Apomorphine induced oral hyperkinesia, non-oral stereotyped, repetitive movements of head, limbs and trunk and increased reactivity. SKF 38393 induced oral hyperkinesia and slight sedation. No non-oral stereotyped, repetitive movements were seen. Conversely LY 171555 produced non-oral stereotyped, repetitive movements, increased reactivity and inhibited the oral movements. Pretreatment with SKF 38393 produced an inhibition of the LY 171555-induced non-oral stereotyped, repetitive movements, and conversely, the SKF 38393-induced oral movements were inhibited by LY 171555. Pretreatment with SKF 38393 produced an inhibition of the apomorphine-induced stereotyped, repetitive movements and oral hyperkinesia. D-1 and D-2 DA receptor agonists appeared to have opposite effects and to antagonize each other. The results indicate that oral hyperkinesia are more related to D-1 receptor stimulation and to a less degree related to D-2 receptor supersensitivity.

Key Words:

• pomorphine
• D-1 agonist
• D-2 agonist
• Stereotypies
• Tardive dyskinesia