中文摘要：

目的：通过体外器官培养系统，探讨甲状旁腺激素相关蛋白（Pamthymid hormone—related protein，PTHrP）在新骨生成和骨组织破坏方面的效应。方法：将全长PTHrP（-36～＋141）cDNA克隆进真核表达载体pcDNA3．1（＋），并用重组质粒pcDNA3．1～阿HrP转染LCC15-MB乳腺癌细胞，在体外器官培养系统里加不同浓度含PTHrP的条件培养上清液培养小鼠颅盖骨。通过组织学方法检测PTHrP141在新骨形成和骨组织破坏方面的效应。结果：转染的乳腺癌细胞产生的PTHrP在低剂量时诱导骨的形成，而高剂量时诱导骨的再吸。结论：PTHrP在新骨的形成和骨组织的破坏方面因其浓詹的不同而且右不同妁府．

英文摘要：

Objective：To determine the role of PTHrP in new bone formation and bone destruction and the mechanisms involved. Methods： LCC 15-MB breast cancer cells were transfected with full-length PTHrP-141 cDNA, and the conditioned medium was collected and cultured with mouse calvarial bones in an in vitro organ culture system. The effects of 1PTHrP-141 on new bone formation and bone destruction were examined by histological examination. Results： PTHrP produced from transfected breast cancer cells induced new bone formation at lower doses and bone resorption at higher concentrations. Conclusion： These results provide direct evidence that PTHrP plays a biphasic role in bone remodeling depending on the concentration administered.