局部注射黄芪多糖对大鼠正畸牙保持阶段BMP-2表达的影响

Local Injection of Astragalus Polysaccharides Influences Expression of BMP-2 in Rats during the Retention Stage after Orthodontic Tooth Movement

目的:探讨局部注射黄芪多糖对大鼠正畸牙保持阶段牙周组织改建和骨形成蛋白2(BMP-2)表达的影响。方法:48只8周龄雄性Wistar大鼠随机分为8组,每组6只,即空白对照组(1组),阴性对照组(1组),实验组(6组)。利用50g牵引力近中移动右侧上颌第一磨牙,建立大鼠正畸牙移动模型,加力21d。实验组于拆除装置前1d开始将10mg/L黄芪多糖溶液局部注射于右上第一磨牙远中颊侧黏骨膜下,每1次/3d,每次50μL;阴性对照组每3d注射等量生理盐水。分别于1、3、7、14、21、28d后处死,测量正畸牙复发距离,采用HE染色观察牙周组织变化,免疫组化染色检测牙周组织中BMP-2的表达。结果:实验组牙周膜宽度保持较好,除1d组外,相同时间的实验组复发距离小于对照组,差异有统计学意义(P<0.05)。在整个保持阶段,对照组远中侧BMP-2表达强度逐渐减少,实验组远中侧BMP-2表达强度逐渐增大。除1d组外,相同时间的实验组BMP-2表达强度显著高于对照组,差异有统计学意义(P<0.05)。结论:大鼠正畸牙保持阶段,局部注射黄芪多糖能够增加牙周组织中BMP-2的表达,从而加速牙槽骨的改建,有利于正畸后牙齿的保持。

Objective：To explore the influence of local injection of astragalus polysaccharides on the expression of bone morphogenetic protein 2in rats during the retention stage after orthodontic tooth movement.Methods：Forty-eight male Wistar rats（8weeks old）were divided into 8groups randomly,each group had 8rats.Eight groups were the blank group（1group）,the control group（CG,1group）and the experimental group（EG,6groups）.The maxillary right first molar mesialization was performed through a 50 g force for 21 days to establish orthodontic tooth movement model.Ten mg/L astragalus polysaccharides（50μL）were locally injected under the distal buccal periosteum of the maxillary right first molar once every three days.The same volume of saline was injected in the CG.These forces were kept for 1,3,7,14,21,28 ds and followed by animal sacrifice.The recurrent distances of the first molars were measured.Morphology changes of periodontal tissue were observed by hematoxylin-eosin staining.The expression of BMP-2in periodontal tissue was determined by immunohistochemistry staining.Results：The width of periodontal ligament in the EG were kept well.The recurrent distances in each group of the EG were shorter than the CG except the 1dgroup（statistically significant differences,P〈0.05）.During the retention stage,the expression of BMP-2was decreasing in the distal side of the CG,while the EG increased.Compared with the EG of the same time,the expression of BMP-2in the EG is notably higher（statistically significant differences,P〈0.05）.Conclusion：Local injection of astragalus polysaccharides can increase the expression of BMP-2 in the periodontal tissue of rats during the retention stage after orthodontic tooth movement,so as to promote the alveolar bone reconstruction,which will be beneficial to the retention of orthodontic treatment.