舒芬太尼对周围神经损伤小鼠脊髓神经元凋亡的影响

Effect of sufentanil on apoptosis in spinal cord neurons of mice with peripheral nerve injury

目的评价舒芬太尼对周围神经损伤小鼠脊髓神经元凋亡的影响.方法清洁级健康雄性BALB∕c小鼠150只,6~8周龄,体重18~22g,采用随机数字表法分为3组(n=50):假手术组(Sham组)、周围神经损伤组(PNI组)和舒芬太尼组(SF组).PNI组和SF组建立单侧坐骨神经损伤模型,造模后SF组腹腔注射舒芬太尼5.0μg∕kg,Sham组和PNI组给予等容量生理盐水,1次∕d,连续3d.于术后1、3、7、14和28d(T0-4)时随机处死5只小鼠取脊髓L4-6节段,HE染色后光镜下观察病理学结果,采用TUNEL法检测神经元凋亡情况,计算神经元凋亡指数(AI).于T0-4时处死5只小鼠取损伤同侧脊髓L4-6节段,采用Westernblot法检测Bcl-2、Bax和活化型caspase-3的表达,计算Bcl-2表达和Bax表达的比值(Bcl-2∕Bax比值).结果与Sham组比较,PNI组和SF组AI升高,Bcl-2表达下调,活化型caspase-3和Bax表达上调(P<0.05);与PNI组比较,SF组AI降低,Bcl-2表达上调,活化型caspase-3和Bax表达下调,Bcl-2∕Bax比值升高(P<0.05).SF组比PNI组神经病理学损伤减轻.结论舒芬太尼可抑制周围神经损伤小鼠脊髓神经元凋亡.

Objective To evaluate the effect of sufentanil on apoptosis in spinal cord neurons of mice with peripheral nerve injury.Methods One hundred and fifty clean-grade healthy male BALB/c mice,aged 6-8 weeks,weighing 18-22 g,were divided into 3 groups(n=50 each)using a random number table method:sham operation group(group Sham),peripheral nerve injury group(group PNI)and sufentanil group(group SF).The model of unilateral sciatic nerve injury was established in PNI and SF groups.After establishing the model,sufentanil 5.0μg/kg was intraperitoneally injected once a day for 3 consecutive days in group SF,while the equal volume of normal saline was given instead of sufentanil in Sham and PNI groups.Five mice in each group were sacrificed at days 1,3,7,14 and 28 after surgery(T0-4),and L4-6 segments of the injure ipsilateral spinal cord were removed for examination of pathological changes(with a light microscope)and for determination of neuronal apoptosis(by TUNEL assay).The apoptosis index(AI)was calculated.Five mice in each group were sacrificed at T0-4,and L4-6 segments of the injured ipsilateral spinal cord were removed for detection of the expression of Bcl-2,Bax and cleaved caspase-3 by Western blot.The ratio of Bcl-2 expression to Bax expression(Bcl-2/Bax ratio)was calculated.Results Compared with group Sham,the AI was significantly increased,the expression of Bcl-2 protein was down-regulated,and the expression of cleaved caspase-3 and Bax was up-regulated in PNI and SF groups(P<0.05).Compared with group PNI,the AI was significantly decreased,the expression of Bcl-2 protein was up-regulated,the expression of cleaved caspase-3 and Bax was down-regulated,the Bcl-2/Bax ratio was increased(P<0.05),and the pathological changes were significantly attenuated in group SF.Conclusion Sufentanil can inhibit apoptosis in spinal cord neurons of mice with peripheral nerve injury.