大鼠脊髓缺血再灌注损伤后MMP-9的基因表达变化

Diversity of expression of MMP-9 mRNA of cellula nervosa in spinal cord ischemical reperfusion injury

目的研究脊髓缺血再灌流损伤过程中的脊髓神经细胞MMP-9表达的变化。方法30只成年Wistar大鼠,解剖分离腹主动脉,按缺血和再灌流各时间段分别阻断开放腹主动脉,造成脊髓腰尾段缺血,假手术组不阻断腹主动脉,取缺血前、缺血30min、缺血60min,缺血30min再灌注2、6、10h后,分别造成脊髓缺血再灌注损伤模型,每个时相点5只。对局部脊髓逆转录PCR(RT-PCR)及荧光定量PCR检测基质金属蛋白酶9(MMP-9)的表达水平。结果正常对照组(缺血前)脊髓可见少量MMP-9表达,而实验组(缺血30min、缺血60min)MMP-9基因表达明显增加,再灌注2、6、10h,MMP-9mRNA表达逐渐增加,且MMP-9的基因表达较缺血期明显增加,各组之间存在明显的差异(P<0.05)。结论MMP-9在脊髓缺血再灌注中起一定作用,再灌注期细胞内MMP-9基因表达明显多于缺血期,MMP-9与缺血再灌注时间之间存在时效关系,表明MMP-9可能参与脊髓再灌流损伤,是脊髓再灌注损伤过程中一个重要的病理学环节,研究结果对于揭示脊髓继发性损伤的发病机理具有积极意义。

Objective To study the diversity of expression of MMP-9 mRNA of eellula nervosa in spinal cord isehemieal reperfusion injury. Methods Model Set-up of isehemie spinal cord injury. Occlusion of the abdominal aorta produced lumbosacral spinal cord isehemia. Abdominal aorta was obstructed and opened according to events of isehemia-reperfusion. The MMP-9m RNA level of eellula nervosa were assessed by reverse transeriptase polymerase chain reaction （RT-PCR）and fluorescent quantitative PCR （FQ-PCR）. Results Normal eellula nervosa express MMP-9m RNA. MMP-9mRNA level was rapidly increased in the 30 min and 60 min of isehemia.In the groups of reperfusion MMP-9m RNA expression level was increased. Their differences were significant （P〈 0.05）. Conclusion There are time correlation in the level of MMP-9m RNA expression and hypoperfusion.Damage of spinal cord tissue in the hypoperfusion phase is serious than its isehemia phase. At the same time,twice lesion of spinal cord has been oeeured by spinal cord hypoperfusion.The level of MMP-9 is one of the important elements of the pathology. All of which are known to be important in the course of spinal cord injury.