降钙素基因相关肽与骨修复及骨重建

骨折的愈合过程是通过一系列复杂的因子来调节完成的，其中，降钙素基因相关肽已经被证实在骨代谢中发挥合成作用。有人发现在骨折局部含降钙素基因相关肽的神经纤维明显增加。降钙素基因相关肽是表达于骨组织的一种重要的感觉神经肽，虽然最初发现其主要作用是扩张血管，增加血流量，但是大量的动物实验结果表明，成骨细胞定向表达降钙素基因相关肽可以增加骨密度，刺激松质骨形成。尤其是降钙素基因相关肽受体在大鼠成骨细胞上的发现，为降钙素基因相关肽具有直接调节骨生长的作用提供了更有力的证据。降钙素基因相关肽也被证明是一种与炎症反应相关的神经肽，有文献报道，骨折时它可以诱发损伤局部炎症细胞浸润。虽然已经认识到降钙素基因相关肽在骨修复及骨重建中的重要作用，但其具体作用机制仍不明了。

Calcitonin gene-related peptide in bone repair and bony remodeling

Fracture healing is regulated by a complex array of factors, of which calcitonin gene-related peptide (CGRP) has been shown to play an anabolic role in bone metabolism. It has been reported that CGRP-containing sensory nerve fibers increased apparently at bone fracture site. CGRP is an important sensory neuropeptides expressed in bone tissue, although the primary function of this neuropeptides is to induce vasodilatation and blood flow, substantial evidence has shown that targeted expression of CGRP to mouse osteoblasts increased bone density, stimulated cancellous bone formation in vivo, especially the presence of CGRP receptors on rat osteoblast provides further evidence for a direct role for CGRP in modulating the function and growth of bone. CGRP is also proved to be a neuropeptide with proinflammatory activities, it may play a direct role in initiating the local inflammatory cell infiltration in the fracture site. Although it has been recognized that CGRP plays an important role in bone repair and reconstruction, the mechanism of this activation still remains to be elucidated.