P物质作为一种神经肽，对骨骼的发育和代谢有重要的调节作用。我们已在前期研究中证实，P物质与髋关节发育不良患者髋脱位程度及关节炎症密切相关。但P物质的表达是否影响髋臼骺软骨的发育及其具体机制目前尚不明确。此外，我们还证实，动态牵张力可抑制成骨细胞miR-103a的表达从而促进成骨，而外源性P物质可上调骺软骨细胞miR-103a的表达。故本课题拟采用髋关节发育不良患者和该疾病的小鼠模型，观察体内P物质、miR-103a的水平与髋臼发育进程、炎症、痛阈等生物学行为之间的关系；然后在细胞水平研究P物质与力学因素对骺软骨细胞成熟、分化和矿化进程的影响；最后在动物水平验证外源性P物质是否通过调节骺软骨细胞miR-103a水平，实现对髋臼发育进程和髋关节血供的调控。因而，深入探讨P物质在髋关节发育不良进程中的作用，为丰富该疾病的发病机制奠定坚实的理论基础和实验依据，并为该疾病的诊治开辟新的思路和途径。

As a neuropeptide, substance P play crucial role in the skeleton development and bone metabolism. In previous study, we have demonstrated that substance P in hip joint is closely related to the dislocation degree and inflammatory environment. However, the mechanism of whether the expression of substance P would affect the development of epiphyseal cartilage in hip joint is still unclear. Besides, we also find the dynamic strain could promote osteogenic differentiation of osteoblast by suppressing the expression of miR-103a, while exogenous substance P could up-regulate the expression of miR-103a in epiphyseal cartilage cells. So, this issue intends to adopt patients and mice with developmental dysplasia of the hip to identify the relationship of endogenous substance P, miR-103a with the development process, inflammation, pain threshold and other biological behaviors. Then we investigate the effect of substance P and mechanical factors on the mature, differentiation and mineralization processes of epiphyseal cartilage cells at the cellular level. Finally, in the animal level, we verify whether exogenous substance P could regulate the development process and the blood supply of hip joint by regulating the levels of miR-103a of epiphyseal cartilage cells. Therefore, the explore of the role of substance P played in the developmental process of hip joint dysplasia would help to lay solid theoretical basis and experimental basis to enrich the pathogenesis process and to open up new ideas and approaches of diagnosis and treatment of the disease.