腹主动脉阻断合并脓毒症大鼠脊髓损伤的实验研究

Experimental study of acute spinal cord injury in rats with lipopolysaccharide infection after abdominal aorta clamping

目的观察大鼠腹主动脉阻断术(AAC)后合并脓毒症时脊髓病理改变及肿瘤坏死因子(TNF)-α的表达。方法 Wistar大鼠32只,随机均分为四组:假手术组(A组),AAC组(B组),LPS组(C组),AAC+LPS组(D组)。所有动物均于再灌注后8h处死,处死前进行后肢神经功能评分,取脊髓行HE染色观察脊髓组织病理损害和免疫组化检测脊髓前角TNF-α的表达。结果 HE染色显示A组损伤较轻;B组可见炎性反应明显,较多神经元坏死;C组有炎性表现,较少神经元坏死,较多运动神经元凋亡;D组可见强烈炎性表现,大量神经元坏死。A组TNF-α少量表达,显著低于其它三组(P<0.01)。C组TNF-α显著高于其它三组(P<0.01)。A、C组后肢神经功能评分显著高于B、D组(P<0.05或P<0.01)。结论 TNF-α在AAC后脓毒症急性脊髓损伤中发挥了重要作用,介导了运动神经元的坏死或凋亡。AAC后机体可存在免疫紊乱,如此时发生脓毒症,TNF-α表达增加可能不如单纯脓毒症明显。

Objective To study the pathological changes and the expression of TNF-α of rat spinal cord after abdominal aorta clamping （ACC） with lipopolysaccharide （LPS） infection. Methods Thirty-two Wistar rats were randomly divided into four groups （the dead were excluded） ： Sham（Group A,n=8） ,AAC （Group B, n=8） ,LPS （Group C, n：8） ,and AAC with LPS infection （Group D, n= 8）. Eight hours after reperfusion, all the rats were excuted and eviscerate the spinal cord tissues. The pathological changes were observed after HE stain, and the expression of TNF-α were detected by immunohistochemistry methods. Results The pathological changes of 4 group： there was slight pathological change and no significant inflammatory reaction in group A. Group B showed slight inflammatory reaction and a small quantity of dynamoneure necrosis. The group C showed an obvious inflammatory reaction and more dynamoneure necrosis. The group D showed an obvious inflammatory reaction and a great quantity of dynamoneure necrosis. The expressional amount of TNF-α in spinal cord showed significant difference between A,C groups and B,D groups（P〈0. 05 or P〈0. 01）. Conclusion TNF-α may play an important role in rat acute spinal cord injury after abdominal aorta clamping with LPS infection. The organism might suffer an immunologic paralysis, if developed a sepsis at this time, TNF-α might not elevate significantly as those simple sepsis.