大鼠创伤性脑损伤后创伤区CD34^+细胞的聚集与脑水肿预后的关系

The correlation between recruitment of CD34^+ cells in injured brain tissue and cerebral edema after traumatic brain injury in rats

目的:初步探讨大鼠创伤性脑损伤(TBI)后创伤区CD34+细胞的聚集与血脑屏障通透性及脑水肿的关系。方法:成年健康雄性SD大鼠108只随机分为假手术组(18只)和TBI组(90只),其中TBI组随机分为伤后1、3、5、7、14 d 5个亚组(每组18只)。采用液压打击法(2.14 kPa)制作TBI模型。用干湿重法及伊文思蓝渗透法分别检测脑水肿及血脑屏障通透性改变情况;应用免疫组化法检测伤侧脑皮质CD34+细胞数。结果:与假手术组相比,伤侧伊文思蓝渗透量和脑水含量均于伤后1 d增加,3 d达高峰,随后逐渐下降;伤侧脑皮质CD34+细胞在伤后1 d下降,从第5天开始增加并超过假手术组;TBI后伤侧脑皮质CD34+细胞数与伊文思蓝渗透量呈负相关,与脑水含量呈负相关。结论:大鼠创伤性脑损伤后创伤区CD34+细胞的聚集与脑水含量的降低有关,有助于缓解脑水肿。

Objective： To preliminarily investigate the correlation of recruitment of CD34＋ cells in injured brain tissue with the permeability of blood brain barrier and cerebral edema after traumatic brain injury （TBI） in rats. Methods： One hundred and eight male Sprague Dawley rats were randomly divided into TBI group （n=90） and control group （n=18）, the TBI rats were randomly divided into 5 subgroup （each group n=18） for analysis on days 1, 3, 5, 7, and 14, respectively. TBI rats were subjected to mild fluid percussion injury. The permeability of BBB was assessed by evans blue method and the brain water content was determined by the method of wet-dry weight. Immuno-histoehemistry was used to detect the number of recruited CD34＋ cells in the damaged cerebral tissue. Results： Compared with surgery controls, both extravasated evans blue and brain water content were increased at dayl, reaching a maximum at day 3, and then gradually decreased. CD34＋ cells decreased at ld, and began to accumulate in the injured brain tissue from day 5. Correlation analysis showed the recruited CD34＋ ceils were negative correlate with both blood brain barrier permeability and brain water content. Conclusion： The recruitment of CD34＋ cells in response to brain injury correlate with reduction of brain water content and may be beneficial for alleviating the cerebral edema.