甲状旁腺激素相关蛋白对发育中的Meckel’s软骨作用的研究

Role of PTHrP in the Development of Meckel's Cartilage

目的观察SD大鼠下颌骨发育过程中甲状旁腺激素相关蛋白(PTHrP)在Meckel’s软骨上时空的变化,初步探讨PTHrP在Meckel’s软骨发育中的意义.方法用免疫组化染色法及原位杂交染色法检测E13-19dSD胎鼠的下颌骨发育过程中,PTHrP及PTHrPmRNA在Meckel’s软骨上的表达.结果 E13-15d在Meckel’s软骨前段PTHrP蛋白强阳性表达,在细胞核、胞浆均表达,在肥大软骨细胞核上表达更明显,而且PTHrPmRNA强阳性表达的位置与PTHrP蛋白一致.E17-19d Meckel’s软骨前段骨化,E17d在临近成骨处的Meckel’s软骨软骨细胞PTHrP蛋白弱阳性表达,且位于肥大软骨细胞核内,PTHrPmRNA阴性表达.E19dPTHrP临近成骨处蛋白染色阴性表达,PTHrPmRNA阴性表达;在前段远离骨化处PTHrPmRNA,PTHrP蛋白强阳性表达,细胞核上表达明显.结论 PTHrP在Meckel’s软骨前段软骨细胞中的表达存在时空特异变化,提示PTHrP蛋白可能由SD大鼠Meckel's软骨软骨细胞合成,并作为一种自分泌因子调节Meckel’s软骨细胞的增殖和分化.

Objective To observe the temporal and spatial changes of parathyroid hormone-related protein（PTHrP）in Meckel＇s cartilage during the development mandible of SD rats,and to explore the role of PTHrP in the development of Meckel＇s cartilage.Method The expressions of PTHrP and PTHrP mRNA in Meckel＇s cartilage during the development mandible of E13-19d SD fetal rats were detected by immunohistochemical staining and in situ hybridization staining.Results During the 13rd and 15th day of the embryo,the strong positive expression of PTHrP was detected in the nucleus and cytoplasm of the preceding Meckel＇s cartilage,and was detected more obvious in the nucleus of hypertrophic cartilage cells.PTHrPmRNA and PTHrP protein were expressed in the same position.During the 17 th and 19th day of the embryo,there were the ossifications of Meckel＇s front-end cartilage.On the 17th day,the weakly positive expression of PTHrP protein was detected in the hypertrophic cartilage nucleus near the Meckel＇s cartilage osteogenesis,and the negative expression of PTHrP mRNA was detected.On the 19th day,the negative expression of PTHrP protein and mRNA were detected.but the strong positive expression of PTHrP protein and mRNA were detected away from the Meckel＇s front-end cartilage osteogenesis,and were significant in the nucleus.Conclusions There are specific temporal and spatial changes on the expressionof PTHrP in the Meckel＇s front-end cartilage chondrocytes.PTHrP is possibly produced by Meckel＇s cartilage chondrocytes,as an autocrine factor regulating Meckel＇s cartilage cell proliferation and differentiation.