RESUMO
OBJECTIVES: In the present study, effects of 3',4'-dihydroxyflavonol (DiOHF) on anxiety-like behavior, and learning and memory were investigated in a model of transient global cerebral ischemia and reperfusion. METHODS: The animals were assigned to sham-operated, ischemia, and two DiOHF-treated (10 mg/kg i.p.) groups. DiOHF was administered at 1 hour before and immediately after the ischemia. Male rats were subjected to bilateral common carotid artery occlusion to induce acute cerebral ischemia for 20 minutes, followed by reperfusion for 7 days. The openfield, elevated plus maze (EPM), and Morris water maze tests were used to evaluate the effects of DiOHF treatment on ischemia-induced locomotor activity, anxiety-like behavior, and spatial and recognition memory impairments, respectively. RESULTS: In the open field test, locomotor activity in the ischemic rats was not altered 6 days after the ischemia, nor was anxiety-like behavior, which was evaluated with the EPM (P > 0.05). In the water-maze test, cerebral ischemia significantly decreased the exploration time in the target quadrant, and the platform crossing counts were lower (P < 0.05) in the probe trial test; this memory impairment was significantly improved by DiOHF applied 1 hour before and immediately after ischemia (P < 0.05). DISCUSSION: All together, these findings suggest that DiOHF reverses spatial learning and memory deficits resulting from transient global ischemia but has no significant effect on anxiety-like behavior.
Assuntos
Antioxidantes/uso terapêutico , Isquemia Encefálica/tratamento farmacológico , Flavonóis/uso terapêutico , Deficiências da Aprendizagem/prevenção & controle , Transtornos da Memória/prevenção & controle , Fármacos Neuroprotetores/uso terapêutico , Traumatismo por Reperfusão/prevenção & controle , Animais , Ansiolíticos/administração & dosagem , Ansiolíticos/uso terapêutico , Antioxidantes/administração & dosagem , Ansiedade/etiologia , Ansiedade/prevenção & controle , Comportamento Animal/efeitos dos fármacos , Isquemia Encefálica/fisiopatologia , Modelos Animais de Doenças , Comportamento Exploratório/efeitos dos fármacos , Flavonóis/administração & dosagem , Injeções Intraperitoneais , Deficiências da Aprendizagem/etiologia , Masculino , Memória/efeitos dos fármacos , Transtornos da Memória/etiologia , Fármacos Neuroprotetores/administração & dosagem , Reconhecimento Fisiológico de Modelo/efeitos dos fármacos , Distribuição Aleatória , Ratos Wistar , Traumatismo por Reperfusão/etiologia , Traumatismo por Reperfusão/fisiopatologia , Aprendizagem Espacial/efeitos dos fármacos , Fatores de TempoRESUMO
The aim of present study was to determine the effect of 3',4'-dihydroxyflavonol (DiOHF) on lipid peroxidation in experimental brain ischemia-reperfusion in rats. Present study was performed on the 34 male Wistar-albino rats, weigth 350-400 g. Experiment groups were designed as 1-Sham; 2-Ischemia-reperfusion; animal were anesthesized and carotid arteried were clemped for 20 min and reperfusion (7 days). 3-DiOHF + Ischemia-reperfusion; DiOHF was given to animals as 10 mg/kg by intraperitoneal. 4- Ischemia + DiOHF + Reperfusion; 5- Ischemia-reperfusion + DiOHF. Blood samples and serebral cortex were analysed for malondyaldehyde (MDA), NO (nitric oxide), xanthine oxidase (XO), glutathione (GSH) and glutathione peroxidase (GPx). Blood MDA levels were significantly higher ischemia-reperfusion groups (P < 0.005). However, DiOHF inhibited MDA. Ischemia-reperfusion led to increased XO and NO but DiOHF supplementation reduced NO and XO. DiOHF increased GSH and GPx levels compared to ischemia-reperfusion group. All together, our present study showed that intraperitoneal DiOHF supplementation has protective effect on brain ischaemia-reperfusion injury in rat.
