【摘要】 目的　观察在快速扩张兔腭中缝的扩张期和固定期血管内皮因子 (VEGF)mRNA表达情况。方法　用螺旋分裂基托扩大矫治器 (Haas矫正器 )扩张兔上牙弓 ,每 12h 0 .2 5mm ,共扩张牵引 14d ,分别于即刻 ,第 1、2、3、4、6周取材 ,标本常规进行逆转录聚合酶链反应 (RT -PCR)检测VEGFmRNA的表达。结果　第 1、2、3、4、6周VEGFmRNA表达量实验组均高于对照组。在实验组VEGFmRNA各组间的变化趋势为随着机械应力快速扩张 ,VEGFmRNA的表达量逐渐上升 ,固定 1周达峰值 ,以后逐渐下降 ,到固定 4周表达水平接近正常。结论　机械牵张力刺激可以导致内源性VEGF生成 ,VEGF可能在缝牵引成骨过程中血管生成及随后的新骨生成过程中扮演重要的角色更多还原

【Abstract】 Objective To investigate the expression of VEGF mRNA during the midpalatal suture and the application of tensile forces in young rabbits. Methods Haas appliance was cemented onto the maxillary posterior dentition. The midpalatal suture was rapidly expanded for 14 days. The animals were sacrificed on 0d, 7d, 14d, 21d, 28d, 42d after the start of activation, respectively. Then, the levels of VEGF mRNA were detected by RT-PCR. Results The expression of VEGF mRNA in the experiment group increased significantly at 7-day’s group and reached peak in 21-day’s group,then gradually decreased. The level of VEGF mRNA was higher than that in the control group. Conclusion Mechanical strain regulates the expression of VEGF at transcription level.更多还原