Neuroprotective effects of resveratrol on ischemic injury mediated by modulating the release of neurotransmitter and neuromodulator in rats

The present study was carried out to elucidate the neuroprotective effect and influence of resveratrol on the extracellular levels of neurotransmitter and neuromodulator during ischemia/reperfusion in rats. Male rats were divided into three groups: sham operation, ischemia treatment, and ischemia combined with resveratrol treatment (resveratrol-treated group, 30 mg/kg intraperitoneally for 7 days). Cerebral ischemia was induced by using the model of middle cerebral artery occlusion. The dialysates in hypothalamus were obtained by brain microdialysis technique. The levels of sixteen amino acids and amines in microdialysate were monitored by capillary electrophoresis analysis. This study shows that the ischemic infarcts were significantly reduced and neurological functions were improved in resveratrol-treated group compared to ischemia group. The analysis results demonstrate that chronic treatment with resveratrol remarkably reduced the release of excitatory neurotransmitter glutamate, aspartate and neuromodulator D-Serine during ischemia and reperfusion; and significantly increased the basal extracellular levels of inhibitory neurotransmitter gamma-amino-n-butyric acid, glycine and taurine. Chronic treatment with resveratrol also ameliorated O-phosphoethanolamine levels and excitotoxic index during ischemia and reperfusion. This study provides the first in vivo evidence that resveratrol could exert neuroprotective effect against ischemia injury by modulating the release of multiple neurotransmitters and neuromodulators during ischemia/reperfusion. (C) 2009 Elsevier Ltd. All rights reserved.