Abstract:

Objective: Periodontal proprioceptional message derived from abnormal occlusion is transmitted via projections from mesencephalic trigeminal nucleus to dorsomedial part of the trigeminal nucleus(Vpdm) and then to ventral posteromedial thalamic nucleus(VPM). To elucidate whether abnormal occlusion will send impact on Vpdm and then on VPM, the expression levels of vesicular glutamate transporter1,2(VGLUT1,2), markers of excitatory nucleus, were detected in Vpdm and VPM of the unilateral anterior crossbite(UAC) treated rats. Methods: The female rats were divided into UAC and control group, and were killed at 2, 4 and 8 week respectively. The expression levels of VGLUT1,2 were detected through immunofluorescence, Western blot and real-time PCR assays. Results: In UAC group, the VGLUT1 protein and mRNA expression levels in Vpdm were increased at all the three time points, while that of VGLUT2 showed no significant differences from the age-matched controls. No such a difference was noticed in the expression levels of VGLUT1,2 in VPM at both protein and mRNA levels. Conclusions: UAC promoted VGLUT1 expression in Vpdm, but showed no significant impact on the expression of VGLUT1,2 in VPM.

Key words: occlusion, dorsomedial part of the trigeminal nucleus(Vpdm), ventral posteromedial thalamic nucleus (VPM), vesicular glutamate transporter (VGULT), trigeminal pathway

摘要：

目的：异常咬合信息可以通过牙周本体感受器、三叉神经系向高级中枢传递，三叉神经感觉主核背内侧部（dorsomedial part of the trigeminal nucleus, Vpdm）-丘脑腹后内侧核（ventral posteromedial thalamic nucleus, VPM）是重要的三叉神经系上传通路，Vpdm是否会受到异常咬合影响，是否继续上传至VPM值得深入研究。本文通过检测单侧前牙反𬌗（unilateral anterior crossbite, UAC）大鼠，Vpdm及VPM中兴奋性神经传导标志物—囊泡膜谷氨酸转运体1,2 （vesicular glutamate transporter1,2, VGLUT1,2）的表达变化，探讨该问题。方法：将雌性大鼠42只分为UAC组和对照组，造模后2、4和8周取材，以免疫荧光、Western blot及实时定量PCR技术，检测目标神经核团中VGLUT1,2的表达差异。结果：UAC组Vpdm内VGLUT1蛋白和 mRNA的表达在各个时间点均明显高于对照组，而VGLUT2 mRNA的表达则无显著性差异。在VPM内，VGLUT1,2的蛋白水平和mRNA水平两组间均无显著差异。结论：UAC促进了Vpdm的VGLUT1表达，但对VPM的VGLUT1,2表达水平没有显著影响。

关键词: 咬合, 三叉神经感觉主核背内侧部, 丘脑腹后内侧核, 囊泡膜谷氨酸转运体, 三叉神经传导通路