EPO对大鼠急性脊髓损伤后Bcl-2及Bax表达与运动神经元凋亡的影响

Influence of Bcl-2/Bax Expressions and the Apoptosis of Motor Neuron in Spinal Cord Injury after Using Erythropoietin

目的:探讨促红细胞生成素对脊髓损伤后脊髓后角Bcl-2、Bax表达及神经元凋亡的影响。方法:120只SD大鼠随机分成4组:空白组、单损组、生理盐水组、EPO组;以T10为中心横断损伤脊髓,EPO组术后即刻给予EPO每日3000U/kg腹腔注射,盐水组腹腔注射等量生理盐水。采用免疫组织化学染色和Tunel法检测损伤后基因Bcl-2、Bax的表达水平和神经元凋亡变化。结果:Bcl-2在1天达高峰,单损组58.32±2.37;EPO组176.68±11.21;3天后开始下降,14天仍有微量表达;EPO组较单损组Bcl-2表达明显增加,EPO组Bcl-2表达比损伤组在相同时间点有明显差异(P<0.05),组内24h时间点较其它点Bcl-2表达均有明显差异(P<0.01)。Bax8h开始增多,24h达峰值,3天开始下降,7天达正常水平。结论:EPO能在SCI后促进Bcl-2、抑制Bax表达,调高Bcl-2/Bax比值,减少继发神经元细胞凋亡,促进神经再生与修复。

Objective ： The observation of the influence of the Bcl-2/Bax expressions and the apoptosis of motor neuron in spinal cord injury after using erythropoietin was made. Method ： One hundred and twenty rats were divided into four groups in random, blank group, single injury group, injury ＋NS group and injury ＋EPO group. EPO was hypodermicaly injected with 3000U/kg once a day in EPO treatment group. The immunohistochemistry and tennel were used to detect the expressions of Bcl-2 /Bax and the apoptosis of motor neuron. Results ： Bcl-2 reached the peak on 1st clay. Single injury group was 58.32± 2.37, EPO group 176.68 ± 11.21. The obviously disparity was in EPO group and others （ P〈0.05 ） .The obviously disparity was in the same group at 24h （ P〈0.01 ） .Bax started to increase at 8h, reached the peak on the second day, started to descend after three days, and reached the normal level at the seventh day. Conclusion ： EPO may promote the expression of Bcl-2 and inhibit the Bax, reduce the apoptosis of motor neuron and promote nerve regeneration and the neurofunctional recovery.