成骨细胞生长与应力之间关系的研究

This study was conducted to implore self-made tooth-borne DO instrument in sheep to study osteoblast function and mechanical stretch. Results showed that by using the instrument, we could effectively lengthen sheep's mandible.In early phrases of DO, mesenchymal cells proliferated and differented into fibroblast-like cells and osteoblasts, whose ultrastructure showed to have active protein synthesis and secreting function. Newly formed collagen, bone canaliculus and the mineration of bone matrix could be clearly observed. Both PCNA and cyclin D1 proteins showed time-dependent characteristics, which indicated that during DO cells greatly proliferated, and cyclin D1 might have some modulating effect on the cell cycle. c-fos gene and phosphotyrosine proteins were expressed in cells of newly formed tissue with time-dependent characteristics, which indicated that they might involved in the signal transduction process of mechanical forces' induction of tissue regeneration. But concrete signals are yet to be studied. By counting the cell numbers under microscope, results showed that BMP-2 and TGF-β1mRNA were time-depentdent, which indicated that they might induce cell proliferation, differentiation and ECM synthesis during DO. BSPmRNA and OPNmRNA were primarily expressed in osteoblasts, and the positive incidence increased during experimental phrase, which indicated that they were connected with the maturation and mineralization of new bone during DO.

本研究拟通过建立机械牵拉力作用下骨延长的动物模型，首次在在体条件下研究牵拉成骨过程中新骨形成的细胞来源、牵拉信号向生物信号转导途径中各组成成分的反应、变化情况；骨形成相关生长因子的表达、成骨细胞结构和功能的改变情况，从组织、细胞、分子三个水平阐明骨延长的机理，从而深入了解牵拉力与骨细胞生长之间的关系。