中文摘要：

目的探讨生长发育期大鼠下颌髁突软骨中甲状旁腺相关蛋白（PTHrP）的表达特征及其季节性变化规律。方法采用64只SD大鼠，随机等量分为白天12h加力组和对照组，应用免疫组织化学技术检测大鼠下颌髁突软骨中PTHrP的表达，图像分析半定量研究PTHrP的季节性变化规律，应用宏观和微观分析法进行统计分析。结果所有大鼠髁突软骨各层细胞中均有PTHrP的表达，并有季节性变化规律。戴用功能矫治器后其表达信号增强。冬末春初增强的最明显。结论生长发育期大鼠下颌髁突软骨中有PTHrP的表达，且表达呈现季节性变化规律。功能矫形治疗可增加大鼠髁突内源性PTHrP的表达，冬末春初效果更明显。

英文摘要：

Objective To study parathyroid hormone-related protein （PTHrP） expression during forward mandibular positioning and compare it with the expression during natural growth in different seasons. Methods Sixty-four SD rats were randomly divided into experimental and control groups. Each group were randomly divided into four groups according to seasons. Immunohistochemical （,IHC） methods were used to test the protein expression of PTHrP. Macroscopic and microscopic approach were applied to analyze the results. Results PTHrP expressed in mandibular condylar cartilage （MCC）, the expression was accelerated and enhanced when the mandible was positioned forward. Furthermore, there was a seasonal rhythm in the protein expression of PTHrP in both experimental and control groups. The protein expression in spring group rose more than other groups. Conclusion The functional appliance therapy can enhance the protein expression of PTHrP. The enhancement has a seasonal rhythm, which indicates that for the functional treatment better results can be achieved in spring.