功能矫治前伸大鼠下颌髁突中甲状旁腺相关蛋白(PTHrP)基因表达的季节性变化规律

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mRNA的表达特征及其季节性变化规律。方法采用SD大鼠，应用原位杂交技术检测大鼠下颌髁突软骨中甲状旁腺相关蛋白的mRNA表达，图像分析半定量研究甲状旁腺相关蛋白mRNA的季节性变化规律，应用宏观、微观分析法进行统计分析。结果髁突软骨细胞中有甲状旁腺相关蛋白mRNA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。一月中旬到二月初增强的最明显。结论功能矫形治疗受季节变化影响，模拟功能矫形治疗的生长发育期大鼠在二月份左右戴用矫治器矫治效果更明显。

Seasonal rhythms in the expression of parathyroid hormone-related protein (PTHrP) mRNA in growing rats after functional mandibular protrusion

Objective To study the expression of PTHrP mRNA(a key growth factor in chondrocyte differention) in condylar cartilage of growing SD rats at different times within one year.Methods Sixty-four SD rats were randomly divided into four groups according to seasonality.Each group included two subgroups: the experimental group and the control group.PTHrP mRNA expression was evaluated by in situ hybridization and analyzed semi-quantitively by image processing.Macroscopic and microscopic methods were applied to assess the results and for statistical analysis.Results PTHrP mRNA was expressed in mandibular condylar cartilage(MCC),which was accelerated and enhanced when the mandible was positioned forward.Furthermore,PTHrP mRNA expression showed seasonal rhythms in all groups with peak values in February.Conclusion Orthopedic treatment of malocclusion with functional appliance has been influnced by seasonality.Better results were achieved in the spring groups for the SD rats.