Modulation of (-)-sulpiride-induced increase in electrically-evoked release of dopamine from rat striatal slices.
(-)-Sulpiride (10 nM-10 microM) in the superfusate, dose-dependently increased the electrically-evoked release of dopamine from rat striatal slices. (+)-Sulpiride had little effect on evoked release of dopamine up to 10 microM. Apomorphine inhibited electrically evoked release of dopamine, and this effect of apomorphine was antagonized by (-)-sulpiride. SCH23390 and forskolin had no effect on the (-)-sulpiride-induced increase in evoked release of dopamine. Treatment with the irreversible dopamine-receptor antagonist N-ethoxycarbonyl-2-ethoxy-1,2-dihydroquinoline caused a significant increase in evoked release of dopamine and prevented the (-)-sulpiride-induced increase in the evoked release of dopamine. These results indicate that the (-)-sulpiride-induced increase in evoked release of dopamine is due to antagonism of the activation of dopamine autoreceptors by endogenously released dopamine.
Yamada
S
S
Institute of Brain Diseases, Kurume University School of Medicine, Japan.
Yokoo
H
H
Nishi
S
S
D000317:Adrenergic alpha-Antagonists / Q000494:pharmacology; D000818:Animals; D001058:Apomorphine / Q000494:pharmacology; D001552:Benzazepines / Q000494:pharmacology; D005576:Colforsin / Q000494:pharmacology; D003342:Corpus Striatum / Q000033:anatomy & histology / Q000187:drug effects* / Q000378:metabolism*; D004298:Dopamine / Q000378:metabolism*; D018492:Dopamine Antagonists; D004347:Drug Interactions; D004558:Electric Stimulation; D007700:Kinetics; D008297:Male; D011804:Quinolines / Q000494:pharmacology; D051381:Rats; D017208:Rats, Wistar; D013469:Sulpiride / Q000494:pharmacology*
D000317:Adrenergic alpha-Antagonists; D001552:Benzazepines; D018492:Dopamine Antagonists; D011804:Quinolines; D005576:Colforsin; C000470:EEDQ; D013469:Sulpiride; D001058:Apomorphine; D004298:Dopamine