大鼠急性放射性脑水肿水通道蛋白4的表达

目的:探讨大鼠伽玛刀照射后诱发急性放射性脑水肿水通道蛋白4(AQP4)表达的变化及其与放射性脑水肿的关系.方法:单次50 Gy伽玛刀照射大鼠大脑半球中线右旁开2 mm(中心点在双外耳道连线上)建立伽玛刀照射模型,用干湿重法和免疫组织化学方法检测照射后不同时间段脑含水量和AQP4的表达.结果:伽玛刀照射后12 h脑含水量和靶区、靶周围区AQP4表达增加,照射后2 d达到高峰,14 d后仍高于正常,AQP4表达的灰度值和脑含水量呈显著负相关(r=-0.9857,P＜0.05).结论:AQP4与急性放射性脑水肿的形成密切相关.

Expression of aquaporin-4 protein in rats with acute radiation-induced cerebral edema

OBJECTIVE: To explore the relation between changes in expression of aquaporin-4(AQP4) protein and acute radiation-induced cerebral edema after Gamma knife radiation. METHODS: The experimental model was established in rats by radiating 2 mm right to median line in cerebral hemisphere with 50 Gy Gamma knife (the center located at the line of auditory canal). The changes of brain water content were measured by the wet and dry weight method. Immunohistochemistry was used to determine the change of expression of AQP4 protein at different periods after Gamma knife radiation. RESULTS: The brain water content and the expression of AQP4 in the target area and the peripheral zone obviously increased at 12 h after Gamma knife radiation, and achieved the peak after 2 d. It was still higher than normal after 14 d. The gray value of expression of aquaporin-4 was negatively related to brain water content (r=-0.9857, P<0.05). CONCLUSION: AQP4 has a close relationship with acute radiation-induced cerebral edema.