前伸大鼠下颌后髁突局部甲状旁腺激素相关蛋白含量的季节性变化规律

Circannual rhythms of parathyroid hormone-related protein in growing rats after functional mandibular protrusion

目的 :探讨不同季节给生长发育期大鼠戴用功能矫治器后 ,其髁突局部的甲状旁腺激素相关蛋白 (PTHrP)含量的季节性变化规律。方法 :选用SD大鼠 ,采用免疫放射法计测大鼠髁突局部甲状旁腺激素相关蛋白含量的变化 ,应用宏观、微观分析法进行统计分析。结果 :生长发育期的大鼠在自然状态下 ,其髁突局部甲状旁腺激素相关蛋白含量存在着季节性变化规律。戴用功能矫治器后 ,其髁突局部甲状旁腺激素相关蛋白含量的季节性变化规律仍存在 ,冬末春初含量最高 ,夏季最低。结论 :季节变化对功能矫形治疗有影响。

Objective:To investigate the levels of parathyroid hormo ne -related protein(PTHrP) in mandibular condylar cartilage during mandible forwar d positioning in different seasons. Methods:64 SD rats were rand omly divided into four groups according to seasons. Orthodontic appliance was us ed in 32 rats for 12 hours each day in daytime for mandibular protrusion. 8 rats were sacrificed at each season time point.Condyle samples were processed for PT HrP detection by a two-site immunoradiometric assay (IRMA) method.Another 32 ra ts without treatment were used as the controls.Macroscopic and microscopic appro ach were applied to analyze the results. Results:The level of P THrP in mandibular condylar cartilage(MCC) in the group of orthodontic treatmen t was higher than that in the control group(P<0.05).In both groups PTHrP lev el in spring was the higherest followed by that in winter, autumn and summer(P <0.05). Conclusion:The functional appliance therapy can enhanc e the levels of PTHrP in the mandibular condylar cartilage. The enhancement has a cirannual rhythm.