title: Investigations into the relationship between the dopaminergic system and ascorbic acid in rat striatum.
abstract: Levels of dopamine (DA), 3,4-dihydroxyphenylacetic acid (DOPAC), ascorbic acid (AA) and dehydroascorbic acid (DHAA) were determined by HPLC in the striatum of male Wistar rats after single or repeated injections of apomorphine (1 mg/kg/day s.c.) and/or haloperidol (1 mg/kg/day i.p.), and 24 h after the last drug administration. Apomorphine significantly reduced the DOPAC/DA ratio and increased the DHAA/AA ratio; these ratio changes were significantly correlated (r = -0.9969, P less than 0.0005). Haloperidol greatly increased the DOPAC/DA ratio; the DHAA/AA ratio was also slightly increased, but there was no significant correlation. When apomorphine was associated with haloperidol, the resulting DOPAC/DA ratio was significantly lower than after haloperidol alone; the DHAA/AA ratio was also significantly reduced in contrast to the effect of apomorphine alone. It is concluded that a non-selective DA receptor activation mediates, in a correlated way, both the inhibition of DA turnover and the increase of AA oxidation in the rat striatum.
authors.affiliation: Institute of Pharmacology, University of Sassari, Italy.
authors.forename: M S
authors.initials: MS
authors.lastname: Desole
authors.forename: M
authors.initials: M
authors.lastname: Miele
authors.forename: P
authors.initials: P
authors.lastname: Enrico
authors.forename: G
authors.initials: G
authors.lastname: Esposito
authors.forename: L
authors.initials: L
authors.lastname: Fresu
authors.forename: G
authors.initials: G
authors.lastname: De Natale
authors.forename: E
authors.initials: E
authors.lastname: Miele
mesh_terms: D000818:Animals; D001058:Apomorphine / Q000494:pharmacology; D001205:Ascorbic Acid / Q000378:metabolism*; D003342:Corpus Striatum / Q000378:metabolism*; D004298:Dopamine / Q000378:metabolism*; D018492:Dopamine Antagonists; D006220:Haloperidol / Q000494:pharmacology; D066298:In Vitro Techniques; D008297:Male; D051381:Rats; D011919:Rats, Inbred Strains
chemical_list: D018492:Dopamine Antagonists; D006220:Haloperidol; D001058:Apomorphine; D001205:Ascorbic Acid; D004298:Dopamine