摘要
目的研究大鼠急性颅脑损伤后病理过程中水通道蛋白-4(aquaporin-4,AQP4)的表达与创伤性脑水肿形成之间的关系。方法成年雄性大鼠60只,伤后4h、8h、24h、48h、和72h组。在大鼠中度冲击加速性损伤模型中,以电镜观察超微结构变化情况,用干湿比重法测脑组织含水量,采用免疫组织化学染色法检测AQP4蛋白表达,并进行脑水肿的相关性分析。结果伤后4h即出现内皮细胞肿胀、紧密连接开放、细胞器变形、血管周围水肿等超微结构损伤征象,脑的含水量亦然(P<0.05),并随时间的推移逐渐加重。同时AQP4的表达呈下降趋势(P<0.001),24h达到最低,48h有所回升,与脑水肿的发生、发展呈负性相关(r=-0.710,P=0.01)。结论大鼠脑外伤后AQP4早期的迅速下调,是机体对脑损伤所作出的一种保护性反应,推测其具有一定阻止血脑屏障破坏、减轻血管源性或细胞毒性脑水肿的作用。
period after Objective To investigate the regularity of aquaporin-4 （AQP4） expression at earlier a traumatic brain injury model in rats, and the correlation with the cerebral lesions. Methods Sisty adult male SD rats were divided randomly into the designated groups, i.e. 4h, 8h, 24h, 48h and 72h after the injury and control groups. A reported impact-acceleration head injury model was used. Edema formation and ultrastructural destruction were assessed by wet-dry weight measurements and the electron microscope respectively. Concurrently, AQP4 protein expression was detected with immunohistochemistry, and analyzed the correlation to cerebral edema. Results 4h after trauma, endothelial cell swelling, tight junction opening, organelle degeneration, and edema surrounding blood vessel could be observed. Water content increased continuously （P 〈 0.05） . In the oedematous contusional cortex, negative immunostaining of AQP4 and down-regulation were indentifled （P〈0.001） at lday post-injury in the right hemispheres. The expression reached the mininmum at 24 hours, and was negatively correlative to cerebral edema （ r=-0.710, P=0.01） . Conelusions Decreasing in AQP4 expression at earlier period after traumatic brain injuries is a protective response by corpse. That may be one of the functions to prevent blood brain barrier destruction and to relieve influences of the vasogenic oedema and cytotoxic oedema.
出处
《锦州医学院学报》
2005年第6期40-43,共4页
Journal of Jinzhou Medical College
