下颌骨牵引成骨过程中VEGF及其受体的表达

目的:通过建立兔下颌骨牵引成骨实验动物模型,研究下颌骨牵引成骨过程中血管内皮生长因子(vascular endothelial growth factor,VEGF)及其受体的表达及意义。方法:选用新西兰白兔30只,随机选取6只动物作空白对照组,24只动物右侧下颌骨植入外置式颌骨牵引器。经7d延迟期后,按1mm/d速率延长下颌骨7d,固定期8周。在延迟期第7d,牵引期第2、4、7d,固定期第1、3、6、8周分别处死3只动物,采用免疫组化方法,检测VEGF及其受体FLT-1(fms-like tyrosine kinase-1)、FLK-1(fetal liver kinese-1)的表达变化。结果:VEGF及其受体FLT-1、FLK-1的表达贯穿下颌骨牵引成骨全过程。下颌骨牵引成骨过程中不同时相多种组织细胞参与表达VEGF及其受体FLT-1、FLK-1,但在表达的变化上存在一定的差异。结论:VEGF通过与其受体特异性结合,在下颌骨牵引成骨血运重建及新骨生成过程中发挥重要作用。

Expression of VEGF and its Receptors in Mandibular Distraction Osteogenesis

Objective: To study the expression of vascular endothelial growth factor(VEGF) and its receptors during mandible distraction osteogenesis(MDO) through establishing a distraction osteogenesis experimental model in rabbit. Methods: Twenty-four rabbits were underwent unilateral mandibular distraction (protocol: 7 days latency period, a distraction at a speed of 0.5 mm per 12 hours for 7days, and a 8 weeks consolidation period). Six rabbits were chosen as control group. Samples were sacrificed at 7th days of latency, 2nd, 4th, 7th day of distraction, and at 1st, 3rd, 6th, 8th week of consolidation. Expression of VEGF and its receptors, fms-like tyrosine kinase (FLT-1) and fetal liver kinase(FLK-1), were detected by immunohistochemistry. Results: VEGF, FLT-1 and FLK-1 were detected in many kinds of cells in distracted area during each time points of MDO. But temporal and spatial of expression of those growth factors and receptors seemed different. Conclusion: VEGF may play an important role by combining with its receptors in angiogenesis and osteogenesis during MDO.