应力刺激对于后纵韧带骨化因子的影响

Influence of different operations on BMP-2,BMP-7 in rat posterior longitudinal ligament

[目的]建立颈椎后路手术动物模型,增加后纵韧带的张力,检测后纵韧带中BMP2及BMP7的表达及水平,探讨机械应力刺激对后纵韧带骨化的作用机理。[方法]SD大鼠100只,分为5组,每组20只,手术方式:(1)颈椎后路全椎板切除组;(2)颈椎后路全椎板切除+肌肉切断组;(3)单纯椎旁肌止点切断组;(4)假手术组,仅作切口,剥离椎旁肌暴露;(5)对照组,不作任何处理。分别于术后1、2、4、8周,取实验动物手术节段后纵韧带标本,PCR方法检测BMP2及BMP7的表达水平。[结果](1)颈椎手术后,全椎板切除+肌肉切断组BMP2,BMP7水平上升最明显,与对照组比较有统计学差异;(2)颈椎后路全椎板切除组BMP2,BMP7水平水平上升,与对照组比较有统计学差异;(3)单纯椎旁肌止点切断组BMP2,BMP7水平上升,与对照组比较有统计学差异;(4)假手术组BMP2,BMP7水平与对照组比较无明显变化。[结论]手术导致的机械刺激提高BMP2,BMP7在大鼠后纵韧带内的表达水平;认为虽然动物模型不能完全模拟人体情况,但是BMP2,BMP7在OPLL的早期可能具有始动作用,而BMP7在后续的骨化过程中可能继续发挥作用。建议临床手术时应尽量采取微创,减少术后不稳增加后纵韧带的应力。

[ Objective] To discuss the initiating and developing mechanism of OPLL, and the influence of different operations on happening and developing of OPLL [ Method ] We subgroup healthy adult S-D rats into groups, did operation on C3-6 level. The first group： laminectomy; the second group： laminectomy and muscle cutting; the third group： muscle cutting only ; the fourth group ： exposure only; contrasting group ： no treatment. We got the tissue of posterior longitudinal, ligament at 1, 2, 4, and 8 weeks post-operation and quantify BMP-2 and BMP-7 by PCR method. [ Result] BMP-2, BMP-7 increased significantly in the 1st, 2nd and 3rd group compared with the contrastinggroup; BMP-2, BMP-7 of only exposure group had no significant difference compared with the contrasting group. [Conclusion] BMP-2 and BMP-7 play important roles in the early stage of OPLL, they could be the on-setting factors of OPLL BMP-7 may play an important roles in the later ossification period.