实验性正畸牙齿移动中RANKL在牙周组织中表达的研究

目的 观察实验性正畸牙齿移动过程中，大鼠牙周组织中转录因子NFKB受体活化剂配体（receptor activator of NF-kB ligand／RANKL）的表达及定位，进一步探讨RANKL的来源、作用机制以及与正畸牙齿移动中骨改建的关系。方法 采用SP免疫组织化学方法检测RANKL在正畸大鼠牙周组织中的表达，并采用计算机图像分析的方法对各组RANKL的表达强度进行半定量分析。结果 实验性正畸牙齿移动过程中：①RANKL主要表达于牙槽骨表达的成骨细胞、破骨细胞和牙周膜成纤维细胞胞浆和胞膜中。②RANKL在牙周组织内的表达和分布在时间上是不均衡的，随时间的增加呈先增高后回降的趋势，峰值在第5天。③RANKL在牙周组织内的表达和分布在部位上是不均衡的，压力侧的表达量高于张力侧，牙槽骨表面的表达量高于近牙骨质侧的牙周膜。结论 RANKL的表达与正畸牙槽骨改建过程中破骨细胞的生命过程密切相关，RANKL通过旁分泌、自分泌机制作用于破骨细胞前体、成熟破骨细胞膜表达的受体RANKL，促进破骨细胞前体的分化、成熟，激活成熟破骨细胞的功能，加速骨改建。

Expression of RANKL in periodontal tissues during experiment movement of rat molars

Objective To investigate the expression and localization of RANKL in periodontal tissues during the experimental movement of rat molars. Methods The force for experimental movement of rat maxillary first molars was 50g and provided by spiral spring. The expression of RANKL was detected with S- P immunohistochemical staining in the control group and groups treated for 1, 3, 5, 7, 14, and 21 days. Results The expression of RANKL was detected weakly in the cytoplasm and membrane of osteoblasts, osteoclast and a few periodontal ligament fibroblasts in normal periodontal tissues. The expression of RANKL in periodontal tissues in experimental group was increased in early stage and peaked at post - treatment day 5 and then gradually decreased to the level of post - treatment day 1. The expression of RANKL on the compression side and the surface of alveolar bone was higher than the tension side and the cementum, respectively. Conclusion RANKL may play an important role in the formation and recruitment of osteoclasts during experimental movement of rat molars.