大鼠轻度脑外伤后水通道蛋白9在大脑皮质及海马的表达变化

目的研究轻度脑外伤（traumatic brain injury，TBI）后水通道蛋白9（AQP9）在脑组织中的表达变化规律，初步探讨AQP9对脑外伤的作用。方法采用Feeney自由落体法制作大鼠轻度脑外伤模型。用TTC法、免疫组织化学法、RT—PCR分别检测脑组织缺血程度、AQP9的表达及双侧大脑皮质和海马AQP9mRNA的变化。结果TTC染色结果显示．损伤早期脑缺血灶不明显，但随时间的推移，逐渐扩大，于72h达最大面积。AQP9及AQP9mRNA表达变化基本一致：TBI后1h，所测区AQP9 mRNA的含量均无明显变化，至3h，双侧大脑皮质及对侧海马AQP9 mRNA的含量明显增高，6h后降低；24h后，双侧大脑皮质及海马均再次明显增高，并于48-72h达峰值。结论TBI早期和继发性损伤期AQP9表达的上调可能分别与TBI应激和能量代谢调节有关。

AQP9 expression in rat cerebral cortex and hippocampus after moderate traumatic brain injury

Objective To observe the expressions of AQP9 and AQP9 mRNA in cerebral cortex and hippocampus of rats after moderate traumatic brain injury(TBI).Methods The moderate TBI model was established according to Feeney's method.At different time points after TBI,the degree of cerebral ischemia by TTC staining,the expressions of AQP9 and its mRNA in brain by immunohistochemistry and RT-PCR respectively were performed.Results No obvious ischemia in brain was found 6 h after TBI,but gradually the ischemic focus enlarged,and reached the maximum 72 h after TBI.The expressions of AQP9 and its mRNA were similar,increasing significantly 3 h after TBI,decreasing 6 h after TBI,then increasing again at 24 h in bilateral cerebral cortex and the hippocampus and reaching the maximum 48 h or 72 h after TBI.Conclusion The increased expression of AQP9 after TBI is involved in the stress of early TBI and in later brain energy metabolism.