title: Correlations between behavioural and oxidative parameters in a rat quinolinic acid model of Huntington's disease: protective effect of melatonin.
abstract: The present study was designed to examine the correlations between behavioural and oxidative parameters in a quinolinic acid model of Huntington's disease in rats. The protective effect of melatonin against the excitotoxicity induced by quinolinic acid was investigated. Rats were pre-treated with melatonin (5 or 20mg/kg) before injection of quinolinic acid (240nmol/site; 1μl) into their right corpora striata. The locomotor and exploratory activities as well as the circling behaviour were recorded. The elevated body swing test was also performed. After behavioural experiments, biochemical determinations were carried out. Melatonin partially protected against the increase of circling behaviour caused by quinolinic acid injection. No alteration was found in the number of crossings and rearings of animals treated with melatonin and/or quinolinic acid. Melatonin decreased the percentage of contralateral biased swings induced by quinolinic acid. Melatonin protected against the increase in reactive species and protein carbonyl levels as well as the inhibition of superoxide dismutase activity resulting from quinolinic acid injection. Melatonin was partially effective against the inhibition of striatal catalase activity and a decrease of non-protein thiol levels induced by quinolinic acid. Melatonin was not effective against the inhibition of Na(+), K(+) ATPase activity caused by quinolinic acid injection. There were significant correlations between circling behaviour and oxidative parameters. The antioxidant property of melatonin is involved, at least in part, in its neuroprotective effect. The results reinforce the idea that melatonin could be useful in overwhelming neurotoxicity caused by quinolinic acid, a rat model of Huntington's disease.
authors: Universidade Regional Integrada do Alto Uruguai e das Missões-Campus Santiago, Santiago, RS, Brazil. ethelwilhelm@yahoo.com.br
authors: Ethel
authors: E
authors: Antunes Wilhelm
authors: Cristiano
authors: C
authors: Ricardo Jesse
authors: Cristiani
authors: C
authors: Folharini Bortolatto
authors: Cristina
authors: C
authors: Wayne Nogueira
mesh_terms: D000818:Animals; D001522:Behavior, Animal / Q000187:drug effects*; D002374:Catalase / Q000378:metabolism; D004195:Disease Models, Animal; D006816:Huntington Disease / Q000139:chemically induced / Q000378:metabolism* / Q000503:physiopathology / Q000517:prevention & control*; D008297:Male; D008550:Melatonin / Q000494:pharmacology*; D009043:Motor Activity / Q000187:drug effects; D017072:Neostriatum / Q000187:drug effects / Q000378:metabolism; D010084:Oxidation-Reduction / Q000187:drug effects; D018384:Oxidative Stress / Q000187:drug effects; D050050:Protein Carbonylation / Q000187:drug effects; D017378:Quinolinic Acid / Q000633:toxicity*; D051381:Rats; D017208:Rats, Wistar; D017382:Reactive Oxygen Species / Q000378:metabolism; D012399:Rotation; D000254:Sodium-Potassium-Exchanging ATPase / Q000378:metabolism; D013438:Sulfhydryl Compounds / Q000378:metabolism; D013482:Superoxide Dismutase / Q000378:metabolism
chemical_list: D017382:Reactive Oxygen Species; D013438:Sulfhydryl Compounds; D002374:Catalase; D013482:Superoxide Dismutase; D000254:Sodium-Potassium-Exchanging ATPase; D017378:Quinolinic Acid; D008550:Melatonin