title: d-Sulpiride inhibits oral behaviour elicited from the nucleus accumbens of freely moving rats.
abstract: The present study analyzed the effect of intra-accumbens administration of the stereoisomers of sulpiride upon (3,4-dihydroxyphenylimino)-2-imidazoline (DPI)-induced changes in oral behaviours and electromyographic patterns of jaw muscles. In line with earlier findings, DPI (5 micrograms) administered into the nucleus accumbens increased chewing and tremor. l-Sulpiride (2-50 ng) had no effect on DPI-induced oro-facial behaviours. d-Sulpiride (10-50 ng) significantly antagonized the DPI-induced increase in chewing and had a biphasic effect on tremor with potentiation (10 ng) followed by attenuation (50 ng). When administered alone, l- or d-sulpiride did not affect oro-facial behaviours. The electromyographic signals, which were analyzed according to a previously described method, were described with the help of three classes: A (the seconds marked by frequency 3 Hz), B (the seconds marked by the frequencies 4-6 Hz); C (the seconds marked by the frequencies 7-15 Hz). DPI enhanced Class B and C of the masseter muscle but did not significantly affect any frequency class of the digastric muscle. l-Sulpiride (2-50 ng) had no effect on DPI-induced (5 micrograms) changes in electromyographic signals. d-Sulpiride (50 ng) antagonized the effects of DPI on Class B of the masseter muscle. Furthermore, d-sulpiride had a biphasic effect on Class C with potentiation (10 ng) followed by attenuation (50 ng). When administered alone, l- or d-sulpiride did not affect the frequency classes of the jaw muscles. It is concluded that d-sulpiride inhibits DPI-induced changes in oral behaviour and electromyographic patterns. It is suggested that d-sulpiride may be effective in the pharmacotherapy of oro-facial dyskinesias in man.
authors.affiliation: Department of Psychoneuropharmacology, University of Nijmegen, Netherlands.
authors.forename: E P
authors.initials: EP
authors.lastname: Prinssen
authors.forename: D J
authors.initials: DJ
authors.lastname: Heeren
authors.forename: A R
authors.initials: AR
authors.lastname: Cools
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D002395:Catecholamines / Q000494:pharmacology; D018491:Dopamine Agonists / Q000494:pharmacology; D018492:Dopamine Antagonists / Q000494:pharmacology*; D004576:Electromyography / Q000187:drug effects; D048288:Imidazolines; D008297:Male; D008410:Masticatory Muscles / Q000294:innervation / Q000502:physiology; D009055:Mouth / Q000502:physiology; D009714:Nucleus Accumbens / Q000502:physiology*; D051381:Rats; D017208:Rats, Wistar; D013237:Stereoisomerism; D013239:Stereotyped Behavior / Q000187:drug effects; D013469:Sulpiride / Q000494:pharmacology*; D014202:Tremor / Q000139:chemically induced
chemical_list: D002395:Catecholamines; D018491:Dopamine Agonists; D018492:Dopamine Antagonists; D048288:Imidazolines; D013469:Sulpiride; C011775:(3,4-dihydroxyphenylamino)-2-imidazoline