摘要
目的 研究后肢缺血预处理对热休克蛋白70在脊髓损伤后表达的影响.方法 SD大鼠随机（随机数字法）分为3组（20只/组）：假手术组大鼠予椎板切除,损伤组大鼠脊髓受到撞击伤（5 g×10 cm）,缺血预处理组在大鼠受到损伤前8 h对下肢进行缺血预处理.损伤通过改良Allen法进行,双下肢痉挛和摆尾为成功标志.缺血预处理通过驱血带阻断下肢血流10 min放开10 min.两侧下肢交替进行,每侧进行3次.在损伤24 h和48 h后,用RT-PCR、免疫组织化学和原位杂交技术,观察HSP70 mRNA及蛋白的变化.各组数据用SPSS 15.0统计软件包进行方差分析（one-way ANOVA）.结果 假手术组大鼠脊髓组织中检测到很弱的HSP70 mRNA表达.损伤和预处理组HSP70表达增强,阳性细胞较多,以中央灰质阳性神经元分布较密集.两个时间点mRNA表达水平预处理组（22.18±3.69,14.15±4.18）高于损伤组（13.97±4.46,8.73±3.55）,差异具有统计学意义（F=16.06,P=0.005和F=7.43,P=0.028）;两个时间点蛋白表达预处理组（16.71±4.02,9.85±2.20）高于损伤组（14.85±3.73,8.78±2.05）差异有统计学意义（F=90.13,P=0.032和F=34.70,P=0.036）.结论 下肢缺血预处理能增加损伤脊髓HSP70的转录和表达,增加神经保护作用.
Objective To observe the effects of ischemic preconditioning of hindlimb （HIP） on the expressions of heat shock protein70 （HSP70） in spinal cord of rats after spinal cord injury （SCI）. Method Sprague Dawleys rats were randomly（ random number） divided into three groups （20 rats in each group）.In sham injury group, rats received laminectomy without SCI; while in the SCI group, rats received traumatic SCI. In HIP group, rats received HIP 8 h before SCI. The SCI animal models were made by using modified Allen＇s weight-drop device （50 g·cm） on L3-L4 vertebrae. HIP was induced by compressing the two lower limbs of rats alternately with a tourniquet for three cycles of ten-minute ischaemia followed by ten-minute reperfusion. Rats were sacrificed 24 h and 48 h after injury separately. The protein and mRNA of HSP70 of involved spinal cord segments were determined by using RT-PCR, hybridization in situ and immunohistochemistry. Results There was weak expression of HSP70 mRNA in rats of sham injury group, and sporadic positive cells in spinal tissue were found by using immunohistochemistry. The expressions of HSP70 mRNA 24 h and48 hours after SCI in HIP group[（22.18±3.69） and （14.15 ±4.18）] were higher than those in SCI group[（13.97±4.46） and （ 8.73 ± 3.55 ）], and the differences were statistically significant （F=16.06, P = 0.005 and F = 7.43, P = 0. 028）. The protein levels of HSP70 24 h and 48 hours after SCI in HIP group [（16.71±4.02） and （9.85±2.20）] were higher than those in SCI group [（ 14.85 ± 3.73）and （8.78 ±2.05）], and the differences were statistically significant （F =90. 13, P =0.032 and F=34.70, P = 0. 036）. Conclusions HIP can increase the transcription and expression of HSP70 in spinal cord of rats following SCI and may have the protective effects on neural tissue.
出处
《中华急诊医学杂志》
CAS
CSCD
北大核心
2011年第4期376-379,共4页
Chinese Journal of Emergency Medicine
基金
国家自然科学基金资助项目（30571878）
江苏省自然科学基金（BK2009101）
