[摘要] 目的：观察正畸牙齿移动不同时期大鼠三叉神经节PPTA mRNA表达变化。方法：采用反转录-聚合酶链反应(RT-PCR)技术检测正畸加力和撤力后不同时期大鼠三叉神经节PPTA mRNA水平的变化情况。结果：加力后2 h大鼠三叉神经节PPTA mRNA的表达量开始增加，加力8 h至加力3 d达到最高，至撤力后2~4周PPTA mRNA的表达量开始下降，但 PPTA mRNA水平仍然明显高于对照组。结论：正畸牙齿移动过程中大鼠三叉神经节PPTA mRNA表达发生了明显的变化。提示P物质可能不仅参与早期正畸牙周组织的炎症损伤过程，而且可能参与了后期的组织修复重建过程。

    [关键词] P物质 前速激肽原A(PPTA) 牙齿移动 三叉神经节 反转录-聚合酶链反应

    Changes in the Expression of PPTA mRNA in the Rat trigeminal Ganglion during and after Tooth Movement.

    SUN Ying-ming, LUO Song-shu, ZHAO Yu-hui.

    Department of Orthodontics,Stomatological Colloge,The Fourth Military Medical University,Xi’an 710032

    [Abstract]Objectives: To investigate the relationship between substance P and orthodontic tooth movement. Methods: The first maxillary molar was moved mesially by an orthodontic force for 2 hours,8 hours,1 days,3 days,1 week and 2 weeks,whereas the other groups were observed after removal of appliances for 1 week,2 weeks and 4 weeks.The expression of PPTA mRNA in trigeminal ganglion were detected with reverse transcription-polymerase chain reaction(RT-PCR). Results: The expression of PPTA mRNA in trigeminal ganglion was stonger than that in control group at all the time points; PPTA mRNA level was increased after 2 hours and reached the peak level around 8 hours-3 days during tooth movement,4 weeks after tooth movement PPTA mRNA level was still higher than that in the controls. Conclusions: The results suggested the involvement of substance P in both early stages of periodontal remodeling and later in the regenerative processes of the periodontal ligament during and after orthodontic tooth movement. ......