Fas抗原及Bax蛋白介导的凋亡在脊髓继发性损伤中的作用  

The role of Fas-and Bax-mediated apoptosis after traumatic spinal cord injury in rats

作　　者：杨海云[1] 柴继宇[2] 朱庆三[3] 

机构地区：[1]天津市天津医院脊柱外科,天津300211 [2]辽宁省葫芦岛市中心医院 [3]吉林大学中日联谊医院骨科

出　　处：《天津医科大学学报》2005年第4期604-607,共4页Journal of Tianjin Medical University

摘　　要：目的:观察脊髓损伤模型中Fas/FasL信号传导系统及Bax蛋白所介导的凋亡过程在SCI继发损伤阶段的作用。方法:Wistar大鼠按Allen法建立脊髓损伤模型,分别在术后1h,8h,2d,3d,7d(n=5)处死取材。分别在每只大鼠脊髓损伤中心区,损伤区头尾3、5、7、10、13mm横截面处各切取3片组织,分别作Bax蛋白,Fas抗原免疫组化,TUNEL法检测凋亡细胞,电镜下观察细胞的超微结构的改变。正常Wistar大鼠作为对照组,分别进行以上各项实验检查。结果:Fas抗原在损伤后8～24h,损伤区头尾侧7mm处出现表达高峰。Bax蛋白在损伤后2～3d,损伤区头尾侧7mm处出现高峰。TUNEL阳性细胞在脊髓损伤2d后在损伤区头尾侧7mm处出现表达高峰,然后逐渐下降。电镜观察:损伤区死亡细胞呈坏死典型表现。而在非损伤区死亡细胞呈凋亡的典型表现。对照组:Bax蛋白,Fas抗原免疫组化均为阴性,未发现TUNEL阳性细胞。结论:证实了Fas/FasL信号传导系统及Bax蛋白介导的凋亡在脊髓继发性损伤中起重要的作用。Objective： To investigate the role of Fas/Fas ligand（FasL） system and Bax/Bcl-2 system as two independent signal transduction pathways leading to apoptosis after traumatic spinal cord injury in rats. Methods： Taumatic injury at T10-T12 level in Wistar rats（180-220 g）was induced by the weight drop device （ALLEN method）.The injuried rats were sacrificed at 1h,8h,1d,2d,3d,7d after injury （n=5 at each time point）. A serials of 10μm cross section were cut at epicenter, 3mm, 5mm,Tmm,10mm,13mm rostal and caudal to epicenter. The immunochemistry for Fas antigen and Bax protein were performed , and TUNEL examination were conducted. Finally ,the morphological features were examined under LM and EM. Uninjuried rats as a control group follow the examination above mentioned. Results： Fas-antigen selectively showed in both injuried and uninjuried areas. The immunoreactivity of Fas-antigen peaked at 7mm caudal and rostral to epicenter 8h-ld post injury.Bax protein shows similar expression pattern, but peaked at 2d-3d TUNEL-positive cell reached their peak at 2 days.EM show the representive nerotic cells in lesioned areas ,but the apoptotic cells at uninjuried areas. Conclusion： The data suggested that, in addition to the immediate damage ,a delayed progressive destructive process that follows cause even more severe spinal cord damage in a way of apoptosis. Fas- and,Bax-mediated apoptosis play an important role during the secondary process.

关 键 词：细胞凋亡 脊髓损伤 BAX蛋白 FAS抗原 

分 类 号：R651.2[医药卫生—外科学] R602[医药卫生—临床医学]