大鼠正畸牙移动过程中ephrinA2在牙周膜内的表达与分布

EphrinA2 expression and distribution in periodontal ligament during orthodontic tooth movement in rats

目的:观察大鼠正畸牙移动过程中牙周膜内ephrin A2的表达分布情况。方法:取36只雄性SD大鼠建立正畸牙移动模型,上颌左侧正畸加力的第一磨牙为实验组,右侧不加力的第一磨牙为对照组。正畸加力后12 h和1、3、7、10、14 d分别将大鼠处死(n=6),解剖分离出含有第一磨牙的牙槽骨并制作石蜡切片,免疫组化染色检测牙周膜中ephrin A2的表达。结果:ephrin A2在对照组牙周膜中呈弱阳性表达,主要分布于成纤维细胞胞质和胞膜上。实验组12 h时牙周膜中ephrin A2表达增强,压力侧显著高于张力侧(P<0.05),主要分布于成纤维细胞、前体破骨细胞的胞膜上,部分分布于胞质和胞核中。阳性表达随正畸加力时间延长而增强,3 d时达到高峰,7 d时开始下降,14 d时接近对照组水平(P>0.05)。结论:ephrin A2在正畸力作用下牙周组织改建中具有重要作用,可能参与了牙槽骨改建的早期调控。

AIM： To investigate the expression and distribution of ephrinA2 in periodontal ligament （PDL） during orthodontic tooth movement in rats. METHODS ： 36 male SD rats were subjected to split - mouth model of or- thodontic tooth movement. Left maxillary first molars of the animals with orthodontic apparatus served as experiment group, while those of the contralateral side with out treatment were served as the control group. At 12 h, 3 d ,7 d , 10 d and 14 d after the placement of orthodontic apparatus, animals （n = 6 ） were sacrificed respectively. The maxillary bone containing the first molar was dissected, the ephrinA2 expression in PDL of was examined by immunohistochemi- cal staining. RESULTS： In control group, ephrinA2 was weakly expressed, mainly in cytoplasm and cell membrane. In experiment group, ephrinA2 expression was significantly increased at 12 h post - orthodontic tooth movement, that in compression side was higher than in stretch side （P 〈 0.05）. EphrinA2 expression increased with the treatment time, reached the peak at 3rd d, began to decrease at 7th d and returned to control level at 14th d. CONCLUSION： Ephri- nA2 plays an important role in periodontal tissue remolding under orthodontic force loading by participating in early alveolar bone remodeling regulation.