夹脊电针对脊髓损伤大鼠内质网应激相关因子IRE1影响的实验研究

Experimental Study on the Apoptosis and IRE1 Protein Expression in Spinal Cord Injury ( SCI) Rats by Electroacupuncture ( EA)

目的:探讨电针对脊髓损伤大鼠细胞凋亡及IRE1蛋白表达的影响。方法:健康雄性SD大鼠132只,随机分为假手术组、模型组、对照组(甲基强的松龙组)、疏波组;每组又分为8 h、3 d、7 d三个时相点。TUNEL原位末端标记法观察脊髓损伤后细胞凋亡情况,Western Blot法观察脊髓损伤后神经细胞内IRE1蛋白表达。结果:模型组及对照组TUNEL染色典型变化为凋亡细胞胞质浓缩,细胞核染色质固缩,呈斑块状聚集于核膜周围。相比对照组,疏波组细胞凋亡程度较轻。脊髓损伤后,IRE1蛋白表达明显上调。甲基强的松龙及电针干预后,各时相点两组IRE1蛋白表达均低于模型组;与对照组相比较,疏波组IRE1蛋白表达上调明显(P<0.05)。结论:电针可能通过降低IRE1的表达来降低脊髓损伤后继发性细胞凋亡,这可能是电针作用机制之一。

Objective： To explore the effect of electroacupuncture on the regulative mechanism of apoptosis and the expression of IRE1 protein in rats after spinal cord injury（SCI）.Methods： 132 healthy SD male rats were randomly divided into Sham group,Model group,Methylprednisolone group,Electroacupuncture（EA） treatment group（Rarefaction Wave group）,with 33 rats in each group.Each group was also randomly divided into three time points（8 h,3 d,7 d）.The apoptosis after spinal cord injured was observed by TUNEL and IRE1 protein expression was observed by Western Blot＇s method.Results： Changes of TUNEL Staining of Model group and Methylprednisolone group were as follows： cell chromatin condensed and aggregated spot-like along Model the nuclear membrane edge with cytoplasm hyperchromia.The degree of apoptosis in Electroacupuncture treatment group was relatively less than the Methylprednisolone group.After spinal cord injury,IRE1 protein degree in Model group was obviously up-regulated.Methylprednisolone group and Electroacupuncture treatment group were less than Model group,which was compared in the degree of IRE1 protein expression in each time point,after Mehylprednisolone and electroacupuncture treatments were intervened.Compared with the Methylprednisolone group,IRE1 protein expression in Rarefaction wave group was significant（P 0.05）.Conclusion： Electroacupuncture treatment can reduce secondary nerve injury after spinal cord injury,and reduce IRE1 expression level,which may be one of the mechanisms.