siRNA沉默水通道蛋白4治疗创伤性脑水肿的实验研究

【目的】应用鼠脑创伤模型观察靶向水通道蛋白4（Aquaporin4，AQP-4）的小RNA干扰（siRNA）技术对脑水肿的治疗效果。【方法】构建沉默AQP-4mRNA表达的siRNA质粒；液压打击法建立大鼠脑创伤（traumaticbraininjury，TBI）模型，分TBI组、空载质粒组和AQP-4siRNA治疗组；提取第1、3、5、7天脑组织总RNA，RT—PCR方法检测AQP-4的mRNA表达；干／湿比重法和Evans蓝测定法观察大鼠TBI后不同时相脑组织含水量和血脑屏障通透性改变；实验动物予以神经功能缺陷综合评分。【结果】RT—PCR结果显示siRNA质粒可有效沉默AQP-4在受损脑组织的表达；与TBI组和空载质粒组比较，AQP-4siRNA治疗组在减少受损脑组织含水量、降低血脑屏障通透性，以及改善动物神经功能方面均有明显好转，各检测时间点与TBI组和空载质粒组比较均存在统计学差异（P〈0．05）。【结论】靶向AQP-4的siRNA技术通过对AQP-4的有效沉默可明显减轻TBI后的脑水肿程度，发挥良好的治疗效果。

An experimental study of siRNA targeting aquaporin 4 treatment on cerebral edema following traumatic brain injury

Objective] Objective To observe the treatment effect of siRNA targeting aquaporin 4 on cerebral edema following traumatic brain injury. Methods] To construct siRNA targeting aquaporin 4, and establish the TBI models in rats. The animals were divided into 3. Results] TBI group, unladen plasmid group, and AQP- 4 siRNA group. Then extracted total mRNA on theist, 3rd, 5th, and 7th day for RT - PCR test. The changes of brain water content and per- meability of blood- brain barrier were measured by the methods of wet and dry weight and Evans blue fluorometry. All the rats were given a mark for their nerve function on the 7th day. Conlusions] RT - PCR results showed that siRNA can effectively silence the AQP - 4 expression in damaged brain tissue. Compared with TBI group and unladen plasmid group, AQP - 4 siRNA group showed a better effect on lessening brain edema level and reducing permeability of the blood - brain barrier, as well as it enhancing rats nerve function. Conclusion The application of siRNA targeting aquaporin 4 may effectively lessen brain edema following traumatic brain injury, and show a good treatment effect.