RESUMEN
Objective To investigate the changes of brain natriuretic peptide (BNP) level in the brain tissues of rats after focal ischemia-reperfusion. Methods Mature male Wistar rats were randomly divided into sham-operated and ischemia-reperfusion groups. Focal cerebral ischemia-reperfusion rat models in the ischemia-reperfusion group were established using Longa's suture-occluded method.And the 2 groups were sub-grouped into 0,3,6,9,12,24,48 and 72 h,and 1and 2 w observation groups according to different times after ischemia-reperfusion. The pathological changes in the brain tissues were observed by HE staining and immunohistochemistry. Results HE staining indicated that neuron degeneration,necrosis and tissue edema could be seen in the brain tissues of rats after ischemic-reperfusion. The BNP levels in the ischemic-reperfusion sub-groups were significantly higher than those in the sham-operative sub-groups at corresponding time points (P＜0.05);and the peak level of edema and BNP expression appeared at 48 h after reperfusion. Conclusion The expression of BNP in the brain tissues of rats after focal cerebral ischemia-reperfusion increases,which might be related to the cerebral edema.