Repeated administration of high dose levodopa enhances hydroxyl radical production in the rat striatum denervated with 6-hydroxydopamine.
We examined whether levodopa (L-DOPA) might increase production of hydroxyl radicals in intact and dopamine-denervated rat striatum. Salicylate trapping combined with in vivo microdialysis provided measurements of 2,3-dihydroxybenzoic acid (2,3-DHBA) as a marker of hydroxyl radical production. Acute administration of high-dose L-DOPA (200, 500 mg/kg, i.p.) did not alter 2,3-DHBA levels in intact striatum or in striatum denervated with 6-hydroxydopamine. On the other hand, L-DOPA administration (200 mg/kg, i.p.) transiently increased 2,3-DHBA in dopamine-denervated striatum of rats after repeated administration of L-DOPA (200 mg/kg, i.p., once daily for 16 days). The results indicated that repeated administration of high dose L-DOPA increased production of hydroxyl radicals in dopamine-denervated striatum.
Ishida
Y
Y
Department of Psychiatry, Miyazaki Medical College, 889-1692, Miyazaki, Japan. ishiday@post.miyazaki-med.ac.jp
Hashiguchi
H
H
Todaka
K
K
Ishizuka
Y
Y
Mitsuyama
Y
Y
D000818:Animals; D003342:Corpus Striatum / Q000187:drug effects* / Q000378:metabolism / Q000502:physiology*; D003714:Denervation; D004334:Drug Administration Schedule; D005260:Female; D017665:Hydroxyl Radical / Q000378:metabolism*; D007274:Injections, Intraperitoneal; D007980:Levodopa / Q000008:administration & dosage*; D016627:Oxidopamine / Q000494:pharmacology*; D051381:Rats; D017208:Rats, Wistar
D017665:Hydroxyl Radical; D007980:Levodopa; D016627:Oxidopamine