关键词: 水通道蛋白质4; 脑缺血; 再灌注; 脑水肿; 大鼠

Abstract: Objective To investigate the Aquaporin-4(AQP-4) expression after cerebral ischemic-reperfussion of rats and the relationship between AQP-4 expression and brain edema.Methods Total 60 adult male Sprague-Dawley rats were randomly divided into sham operation group and middle cerebral artery occlusion/reperfussion(MCAO/R) group. All the rats were tested for neurological behavior by using three different methods: Longa, Berderson and balance beam tests. Brain water content was measured by the wet-dry method and we observed the pathology changes by hematoxylin and eosin(HE) dyeing,the expression of AQP-4 by immunohistochemistry staining.Results In MCAO/R group: the behavioral outcomes were most serious at 48 h and 72 h , back to normal at 7 d; the brain water content increased at 24 h[(82.42±0.12)%], reached to maximum at 48 h [(85.40±0.10)%]and continued to 72 h [(84.87±0.15)%],decreased to normal at 7 d; conspicuous edema and inflammatory cell infiltrating observed by HE dyeing, were most obviously at 48 h and 72 h but disappeared at 7 d; the expression of AQP-4 gradually increased at 6 h (110.0±4.4), reached its peak at 48 h - 72 h (126.2±2.6; 140.1±1.2), and reduced at 7 d (111.3±8.0), but also higher than sham operation group significantly, P<0.05.Conclusion The phase consistency is obvious between the change of expression of AQP-4 and dynamic state process of brain edema, which suggest AQP-4 probable take effect in pathophysiological course of brain edema in the early phase of phase of cerebral ischemic-reperfusion. And inthe late phase AQP-4 may play an important role in the clearance of redundant brain water.

Key words: Aquaporin-4; Brain ischemia; Reperfussion; Brain edema; Rat