甲状旁腺激素相关蛋白mRNA在髁突软骨与生长板软骨发育早期的表达变化

目的研究甲状旁腺激素相关蛋白(parathyroid hormone-related protein,PTHrP)mRNA在髁突软骨与生长板软骨发育早期的表达变化,初步探讨PTHrP在软骨内成骨中的作用。方法选用胚胎SD大鼠的髁突软骨与生长板软骨作为研究对象,采用原位杂交染色法检测发育早期两种软骨内PTHrP mRNA表达,以图像分析仪进行图像分析。结果胎龄14～19 d,随着软骨发育的成熟,PTHrP mRNA在生长板软骨和髁突软骨中的表达越来越广泛并呈现一定的时空变化,但PTHrP mRNA在两种软骨中的表达部位存在一定的差异。在髁突软骨中,PTHrP mRNA在增殖层和前肥大层强表达;在生长板软骨中,其主要表达在软骨膜细胞和关节周围的软骨细胞,前肥大层中也有较强的表达,增殖层弱表达或不表达。结论 PTHrP mRNA在生长板软骨和髁突软骨中表达部位不同,但均呈现一定的时空变化,提示PTHrP对不同分化阶段的软骨细胞具有一定的调节作用。

Comparison of PTHrP mRNA expression between mandibular condyle cartilage and growth plate cartilage in the early development

Objective To inwestigate the different expression of PTHrP mRNA between condyle cartilage and growth plate during the early stage of development, to discuss the effects of PTHrP mRNA in endochondral ossification. Methods Condyle, cartilage and growth plate were gained from Sprague Dawley rat fetuses respectively on embryonic day 14 （El4 d） , El5 d, El6 d, El7 d, El8 d and El9 d. In situ hybridization （ISH） was used to detect the expression of PTHrP mRNA, and the expressions were obtained by patho-image-analysis. Results Dm＇ing El4 d-E19 d, the expression of PTHrP mRNA spread wider with development and presented space-lime change in both condyle cartilage and growth plate cartilage, but there were still some differences in PTHrP mRNA distribution between them. In condyle cartilage, PTltrP mRNA were highly localized at proliferative ehondroeytes and prehypertrophie ehondroeyles, and FFHrP mRNA weakly localized at hypertrophic ehondroeyles, while in growth plate, it was not the same. Conclusion There are some differences between condyle cartilage and growth plate in the expressions of PTHrP mRNA, but the expression of PTHrP mRNA presented a space-lime change, these results suggested that PTHrP modulates the function of ehondroeytes.