脑出血脑组织中水通道蛋白4的极性表达缺失

Loss of aquaporin 4 polarized expression in the brain following intracerebral hemorrhage

摘要:

目的：观察脑出血（intracerebral hemorrhage，ICH）大鼠脑组织中水通道蛋白4（aquaporin 4，AQP4）的极性表达变化情况，以初步探讨其在出血性脑水肿中的作用。方法：SD大鼠随机分为sham组和ICH组，采用自体血注入法建立大鼠ICH动物模型，应用核磁共振成像检测血肿产生及发展情况，干湿重法检测脑水含量变化以及免疫荧光检测AQP4的极性表达变化情况。结果：ICH后1 d，血肿体积最大，脑水含量达到峰值，高达（79.769±0.710）%，差值具有统计学意义（P=0.000）；血肿周围组织中AQP4极性表达缺失，AQP4表达在星胶细胞胞体和突起上，而sham组中AQP4则极性表达在星胶细胞终足膜上。结论：ICH后血肿周围组织中AQP4极性表达缺失，后者可能促进了出血性脑水肿的发生。

Abstract:

Objective：To observe the changes of aquaporin 4（AQP4） polarized expression in the brain following intracerebral hemor－rhage（ICH），and to explore its roles in the brain edema following ICH. Methods：Rats were randomly divided into ICH group and sham group；and autologous blood was injected into the right caudate nucleus to establish ICH model in rats. The hematoma volume was mea－sured by magnetic resonance imaging，the brain water content（BWC） was measured by the wet and dry weight methods，and the po－larized expression of AQP4 was detected by immunofluorescence. Results：On d1 post ICH，the hematoma volume reached the peak，the BWC reached its maximal value（79.769±0.710）%，and the difference between the sham group and the d1 post-ICH group was statistically significant（P=0.000）. In the perihematomal tissue，the polarized expression of AQP4 was lost，and AQP4 was expressed in astrocytic soma. However，in the sham tissue，AQP4 was polarized expressing in astrocytic end-foot membrane. Conclusion：In the per－ihematomal tissue of brain following ICH，the polarized expression of AQP4 is lost，which may contribute to the formation of brain ede－ma following ICH.