颈动脉内膜切除后基质金属蛋白酶9动态表达对早期血管再狭窄形成的意义

背景：颈动脉内膜切除后发生血管再狭窄是影响治疗效果的重要因素。目的：观察颈动脉内膜切除后基因基质金属蛋白酶9 mRNA动态表达在早期血管再狭窄发生中的意义。设计、时间及地点：随机分组设计，对比观察，实验于2006-02/2007-12在解放军北京军区总医院完成。材料：健康雄性新西兰兔41只，体质量3.0 kg左右，其中36只用于制备颈动脉粥样硬化性狭窄模型。方法：将41只新西兰兔分为2组，对照组(n=5)：不做任何干预。实验组(n=36)：于造模后4 h，1，3，7，30，90 d 6个时间点各取6只，以40 g/L多聚甲醛灌注固定取材，行常规病理切片苏木精-伊红染色观察形态变化。主要观察指标：采用实时定量-聚合酶链反应技术观察术前即刻、术后1，3，7 d颈动脉内膜切除后基因基质金属蛋白酶9 mRNA在早期血管再狭窄过程中的表达变化。结果：颈动脉内膜切除后内膜修复过程大体上可以分为血栓形成阶段，炎症反应阶段，内皮修复阶段，血管平滑肌增殖阶段，基质形成、堆积阶段。基质金属蛋白酶9 mRNA水平在术后1 d开始表达，术后3 d达峰值，术后7 d显著回落。结论：基质金属蛋白酶9对早期血管平滑肌细胞的增殖、迁移，介导的局部血管重建和再塑，对血管再狭窄的形成有重要作用。

Role of matrix metalloproteinase-9 dynamic expression in the development of early vascular restenosis after carotid endarterectomy

BACKGROUND: Vascular restenosis after carotid endarterectomy (CEA) is an important factor affecting curative effect of operation.OBJECTIVE: To explore the role of matrix metalloproteinase-9 (MMP-9) mRNA dynamic expression in the development of early vascular restenosis after carotid endarterectomy. DESIGN, TIME AND SETTING: A random grouping contrast observation was completed in the General Hospital of Beijing Military Area Command of Chinese PLA from February 2006 to December 2007.MATERIALS: Forty-one healthy male New Zealand rabbit, weighing about 3.0 kg, with 36 ones used for preparing carotid atherosclerotic stenosis (CASS) models.METHODS: The 41 New Zealand rabbits were divided into two groups. In control group, rabbits (n=5) received no intervention. In experimental group, each 6 of the CASS rabbit models (n =36) were selected at the time points of hour 4, day 1, 3, 7, 30, and 90 following CEA respectively. Then they were fixed with 40 g/L polyoxymethylene perfusion and stained with hematoxylin-eosin to observe their morphologic changes.MAIN OUTCOME MEASURES: The expression changes of MMP-9 mRNA were observed during the development of early vascular restenosis by the quantitative real-time polymerase chain reaction technique preoperatively as well as at day 1, 3 and 7 following CEA.RESULTS: Several stages could be seen in the reparative process of neointima after CEA, including the thrombosis, the inflammatory reaction, the repair of endothelium, the proliferation of vascular smooth muscle cell, the formation and accumulation of extracellular matrix. MMP-9 mRNA was expressed since day 1, reached a peak at day 3 and then decreased significantly at day 7 postoperatively. CONCLUSION: MMP-9 plays an important role in the proliferation, migration and reconstruction of vascular smooth muscle cells, the mediated reconstruction of local blood vessels, as well as the development of vascular restenosis.