摘要
目的观察汉防己甲素(tetrandrine,Tet)对大鼠急性脊髓损伤后bcl-2和bax表达的影响,探讨其对脊髓损伤的作用机制。方法成年SD大鼠100只,分为4组:假手术组10只,损伤对照组、甲基强的松龙(methylprednisolone,MP)治疗组、Tet治疗组各30只。胸8、9椎板切除后,损伤对照组,MP、Tet治疗组用加速压迫型Allen’s打击法制成脊髓损伤模型,后2组动物于制模前,伤后24、48h尾静脉分别注射MP90mg/kg和1%Tet22.5mg/kg。各组大鼠于术后8h,1、3、7、14d行运动功能BBB评分,取损伤段脊髓行石蜡切片HE染色,观察脊髓组织的形态结构变化,免疫组织化学染色检测细胞凋亡因子bcl-2、bax表达。结果伤后7、14dMP、Tet治疗组大鼠运动功能评分显著高于损伤对照组(P<0.05),各时间点MP、Tet治疗组评分无统计学意义(P>0.05);MP、Tet治疗组脊髓组织损害较损伤对照组轻,术后8h至14d动态观察,3～7d损伤表现最为严重,达到损伤高峰期;假手术组中bax、bcl-2阳性细胞数较少,MP、Tet治疗组bax阳性细胞数少于损伤对照组(P<0.05),而bcl-2阳性细胞数多于损伤对照组(P<0.05)。结论 Tet可通过增加bcl-2表达和降低bax表达来抑制急性脊髓损伤后神经细胞的凋亡,有益于脊髓组织的保护,促进运动功能的恢复。
Objective To observe the influence of tetrandrine （Tet） on the expressions of Bcl-2 and Bax in rats with spinal cord injury. Methods A total of 100 SD rats were randomly divided into sham-operation group （group A,n=10）,spinal cord injury group （group B,n=30）,methylprednisolone group （MP） group （group C,n=30） and Tet group （group D,n=30）. The modified Allen method was adopted to establish the models of T9 spinal cord injury in groups B,C and D. The animals of group D received 1% 22.5 mg/kg Tet through tail vein in 24 and 48 h after operation,those of group B were injected with normal saline at same volume as in group D,and the rats from group C were given a tail vein injection of 90 mg/kg MP before and 24 and 48 h after injury. BBB score was recorded at 8 h,and 1,3,7 and 14 d after operation. Six rats from each group were killed immediately after BBB scoring,and the samples were taken from the spinal cord injury sites for HE staining. The expression levels of Bcl-2 and Bax proteins in the obtained samples were studied with immunohistochemical assay. Results The BBB score of groups C and D were significantly higher than that of group B at day 7 and 14 （P0.05）. There was no significant difference in the score between groups C and D at each time points （P0.05）. HE staining showed the spinal cord of groups C and D had fewer necrosis than that of group B （P0.05）. The injury was most severe in day 3 to 7. The number of Bcl-2 positive cells in groups C and D were larger than those of group B at each time points （P0.05）. However the number of Bax postive cells in groups C and D were less than those of group B at each time points （P0.05）. Conclusion Tet is able to protect neurons from apoptosis and promote the nerve function recovery by inhibiting the expression of Bax and promoting the expression of Bcl-2.
出处
《第三军医大学学报》
CAS
CSCD
北大核心
2010年第12期1321-1324,共4页
Journal of Third Military Medical University
基金
贵州省省长基金(2005-27)
贵州省卫生厅基金(2003-150)~~
