水通道蛋白-4在正常大鼠脑内的分布研究

Distribution of Aquaporin 4 in normal rat brain

目的 明确正常大鼠脑内水通道蛋白-4(AQP4)的表达与分布,为进一步研究提供理论依据。方法 采用AQP4单克隆抗体,对正常SD大鼠脑的冰冻切片进行免疫组织化学检测AQP4蛋白的表达水乎。结果 免疫组织化学染色结果显示阳性着色细胞主要有胶质细胞、毛细血管内皮细胞、脑室室管膜上皮细胞,其次为脑室脉络丛上皮细胞,着色部位主要在细胞膜,其中在胶质细胞表现出一定的方向性,主要分布在与毛细血管内皮细胞接触的一侧。结论 AQP4在正常大鼠脑内具有广泛的表达,主要表达分布于与血脑屏障相关的毛细血管内皮细胞及其相连的胶质细胞,其次是脑室室管膜上皮细胞、脉络丛上皮细胞。依据结构与功能相联系的原则,其表达的解剖分布提示AQP4在脑内主要参与脑内水代谢的调节。

Objective To examine the distribution of Aquaporin 4 (AQP4) in normal rat brain. Methods Immunohistoehemistry staining with anti-AQP4 monoclonal antibody provided by ADI(USA) were performed on frozen brain tissue slices from healthy adult SD rats to detect the expression level of AQP4. Results Immunohistochemistry staining showed that most cells staining positive were glia cells, capillary endothelial cells,ependymal cells of cerebral ventricle, and epithelium of choroids plexus. All the positive cells were stained at cell membrane. Most importantly, on glia cells the expression of AQP4 was mainly on the side of cell membrane contacting with capillary vessel endothelial cells. Conclusion AQP4 was widely expressed in rat brain, highly related with endothelial cells and glia ceils, which were closely connected with blood brain barrier,and also related with ependymal cell of cerebral ventricle and epithelium of choroids plexus. Taken together, all the data here suggested that AQP4 was involved in cerebral water metabolism and might regulate systemic water metabolism.