CY 208-243, a novel dopamine D-1 receptor agonist, fails to modify dopamine release in freely moving rats

CY 208-243, a novel D-1 agonist structurally unrelated to other D-1 agonists, at doses which elicited behavioural stimulation with locomotion, sniffing and grooming, failed to modify the release and metabolism of dopamine (DA) in the nucleus accumbens and in the dorsal caudate of freely moving rats, as estimated by transcerebral dialysis. CY 208-243 prevented the increase of DA release and metabolism elicited by the specific D-1 antagonist, SCH 23390, but not by the specific D-2 antagonist, sulpiride. The results support the conclusion that CY 208-243 is an effective and specific D-1 agonist in vivo.