马尾神经受压致腰椎管狭窄模型大鼠脊髓P物质不同时程的表达特征(英文)

Expression characters of substance P in rats with lumbar spinal stenosis cansed by cauda equina compressions model

背景:疼痛递质-P物质的表达变化与腰椎管狭窄症所引发的持续性腰腿痛密切相关。但缺乏对马尾神经受压所致腰椎管狭窄模型大鼠脊髓P物质不同时程变化的定性与定量参数的了解。目的:探讨腰椎管狭窄时不同时程脊髓内P物质的表达变化。设计:随机分组对照实验。单位:中国医科大学附属第一医院骨科。对象:实验于2003-02/2004-12在中国医科大学实验动物中心完成。选择成年雄性SD大鼠30只。随机分为5组,1组为正常对照组。其他4组按取材时间不同分为2,4,8,12周组,每组6只。方法:制备大鼠马尾神经受压后的腰椎管狭窄模型,于2,4,8,12周进行取材。应用免疫组化染色方法检测不同时间脊髓中P物质的表达。以光镜下神经元细胞核蓝色着色,细胞浆出现棕褐色颗粒定为P物质表达阳性。每例切片在脊髓横断面随机选取5个高倍视野,计数阳性细胞数。主要观察指标:不同时间脊髓后角中P物质的阳性细胞的表达。结果:在整个实验过程中无动物死亡,全部进入结果分析。①正常对照组偶见神经元细胞阳性着色,但着色较浅。②术后2周组可见大量神经元细胞阳性着色,着色深,阳性细胞数5.08左右。③术后4,8,12周组P物质染色有一定波动,较2周组阳性细胞数降低。但2,4,8,12周组脊髓后角P物质阳性细胞数目均显著高于对照组犤(5.08±0.41),(4.02±0.35),(2.58±0.33),(3.45±0.22),(0.85±0.23),t=6.85,5.90,3.49,6.85,P<0.05或P<0.01犦。结论:腰椎管狭窄症中马尾神经受压后,不同时程脊髓P物质的阳性细胞数的表达均有不同程度的增高。这种表达是否与伤害性刺激持续传入导致P物质上升,对减轻脊髓水肿和发挥对神经元的保护作用是否有关,有待进一步认证。

BACKGROUND: As a pain-related peptide, substance P is closely related with sustained pain in low back and lower extremities caused by lumbar spinal stenosis.However, the expression of substance P in the rat with cauda equina compression rat is not reported. OBJECTIVE: To investigate the content of substance P in spinal cord of rat with lumbar spinal stenosis at different stages. DESIGN:A randomized and controlled experimental study. SETTING:The Orthopedic Department of the First Affiliated Hospital of China Medical University. MATERIALS: The trial was conducted in the Experimental Animal Center of China Medical University within the period from February 2003 to December 2004.Thirty mature male SD rats were randomly and averagely assigned into five groups.One group served as control and in the other four experimental groups the content of substance P of the rats were examined in the 2nd,4th,8th and 12th respect week respectively. METHODS:The model of lumbar spinal stenosis was established by compressing cauda equina in rats.The spinal cords were harvested in the 2nd, 4th,8th and 12th respect week respectively for immunohistochemical determination of the expression of substance P (SP) in the posterior horn. MAIN OUTCOME MEASURES:The expression of substance P in the posterior horn at different times. RESULTS:All rats were included in the analytic stage.①There were few slightly-stained neurons in the control group. ②There were large amount of deeply-stained neurons in the 2nd week group. The mean positive neuron number was about 5.08.③The stained neurons in the 4th,8th and 12th week group varied within a certain range and were less than that of the 2nd week group.But they were all more than that of the controls[(5.08±0.41),(4.02±0.35),(2.58±0.33),(3.45±0.22)vs(0.85±0.23),t =6.85,5.90,3.49,6.85,P< 0.05 or P< 0.01]. CONCLUSION:The expression of substance P increases when the cauda equina is compressed. Whether this is because the harmful stimuli increases SP expression and the latter in turn protects spinal cord by reducing the edema of spinal cord warrants more studies.