不平衡咀嚼肌力作用下髁突软骨下骨中OPG/RANKL的表达

摘要

Objective To build an animal model to investigate the effect of Muscles' Imbalance on the bilateral condylar subchondral bone.Methods 32 male rats were randomly divided into excise the coracoid and botulinum neurotoxin A masseter injection group and control group.Each group of 16 SD rats were performed the corresponding operation on the right side.The rats were killed at the end of the 2th,4th,8th and 12th weeks,acquire TMJ condylar and observe its Histological changes.The expression of OPG and RANKL in condylar subchondral bones was observed by immunohistochemical staining.Results Immunohistochemical showed:After 2 weeks,the expression of OPG in the experimental groups were higher thanthat ofblank control group (P ＜ 0.05),and had no statistical difference with blank control group after 4,8,12 weeks (P ＞ 0.05).The expression of RANKL were higher than that of blank control group after 2 and 4 weeks (P ＜ 0.05),and had no statistical difference with blank control group after 8,12 weeks (p ＞ 0.05);The ratio of OPG/RANKL in experimental groups were lower than those ofthe blank control group after 2,4 weeks (P ＜ 0.05),and had no statistical difference with the blank control group after 8,12 weeks (P ＞ 0.05).Conclusions By OPG/RANKL signaling pathways,excise the coracoid and botulinum neurotoxin A masseter injection involved in pathologic reconstruction of the bilateral TMJ condylar subchondral bone.%目的 探讨不平衡咀嚼肌力对髁突软骨下骨OPG/RANKL表达的影响.方法 选取雄性SD大鼠32只,经随机抽样分成实验组(喙突切除+咬肌阻断组)以及空白对照组,每组16只,并行右侧手术建立SD大鼠不平衡咀嚼肌力动物模型.通过单侧手术切除颞肌和肉毒神经毒素A注射咬肌,建立不平衡咀嚼肌力SD大鼠动物模型,分别于建模后2、4、8、12周处死动物,免疫组织化学检测OPG和RANKL在大鼠髁突软骨下骨中的表达.结果 髁状突软骨下骨中OPG和RANKL共同表达在成骨细胞、破骨细胞和早期骨细胞中;OPG表达在术后2周时实验组高于空白对照组(P＜0.05),术后4、8、12周时与空白对照组差异无统计学意义(P＞0.05);RANKL表达在术后2、4周时实验组高于空白对照组(P＜0.05),术后8、12周时与空白对照组差异无统计学意义(P＞0.05);OPG/RANKL的比值在术后2、4周时实验组低于空白对照组(P＜0.05),术后8、12周时与空白对照组差异无统计学意义(P＞0.05).结论 单侧喙突切除和咬肌阻断引起的双侧颞下颌关节应力改变,可早期引发髁突软骨下骨的异常改建,OPG/RANKL信号通路介导了应力对髁突软骨下骨的改建.