持久脊柱负荷与椎间盘组织中MMP-2表达关系的研究

目的：建立一压力可控型椎间盘退变模型,并探讨持久的脊柱负荷对椎间盘MMP-2表达的影响。方法：选用54只成年Wistar大鼠随机分为三组,分别模拟人类在站立（A组1.12N）、坐位直立（B组1.68N）、坐位前屈（C组3.08N）三种状态下椎间盘内的负荷情况,给予大鼠尾椎Co9/10椎间盘恒定压力加压,以相邻Co8/9椎间盘不加压作为对照（D组）。三组分别在3、7、14天后取受压及对照椎间盘标本,进行HE染色组织学观察及免疫组织化学分析,观察椎间盘退变情况及MMP-2在椎间盘组织中的含量变化。结果：随时间与压力的增加,椎间盘组织学评分与MMP-2表达增高（P〈0.05）,MMP-2表达与椎间盘退变程度成正相关（r=0.870,P〈0.05）。结论：持久的脊柱负荷可引起椎间盘退变及MMP-2表达增加,MMP-2可能在椎间盘退变的过程中发挥重要作用。

Relationship Between Prolonged Spinal Loading and Expression of MMP-2 in Intervertebral Discs

Objective： To establish an in vivo mouse model of compression-control degeneration and to investigate the effects of prolonged mecanial loading on MMP2.Methods： A total of 54 adult Wistar rats were randomly divided into three groups,group A： the pressure was 1.12N（simulating human pressure of the disc when human stand）,group B： the pressure was1.68N（simulating human sit-ting）,group C： the pressure was 3.08N（simulating human sitting flexion）.Group D： control group without any pressure to the disc.Static compression was applied to mouse coccygeal discs in vivo for 3,7,or 14 days.The expression of MMP-2 in four groups were detected by immunohistochemical technique.Results： The degeneration of disc and the expression of MMP-2 increased with the increasing of the time and pressure（P 0.05）,and a positive correlation was observed between the degeneration grade of disc and the amount of MMP-2（r=0.870,P0.05）.Conclusion： Prolonged spinal loading cause the disc degeneration and the increasing expression of MMP-2,MMP-2 may be one of the important factors leading to intervertebral disc degeneration.