摘要
目的：探讨持续动态压应力环境下骨折愈合时骨痂软骨内成骨的特点以及前列腺素E2（PGE2）和环磷酸腺苷（cAMP）的含量变化。方法：新西兰兔行单侧肱骨干横断截骨，实验组以天鹅记忆接骨器内固定，在骨折端造成持续动态压应力．对照组以加压钢板固定。分别于术后第3、7、14、21、28、56、84日在骨折间隙内取材，行组织学、放射免疫和RT-PCR等检测。结果：两组PGE2和cAMP含量均较骨折前显著上升，且术后3～4周时实验组明显高于对照组。组织学和RT-PCR结果则显示实验组骨折间隙内软骨痂基质的钙化、软骨内成骨及编织骨痂的改建均领先于对照组。结论：天鹅记忆接骨器产生的持续动态压应力可以促进骨痂细胞外基质的钙化和软骨内成骨，从而加速骨折愈合，且PGE2和cAMP很可能介导了这一成骨效应。
Objective： To explore the effect of continuous dynamic pressure stress produced by shape memory connector （SMC） on callus endochondral bone formation and PGE2 and cAMP contents during experimental fracture healing. Methods.. Unilateral osteotomy of left humeral diaphysis was performed in 80 adult New Zealand rabbits. The humeral frac- ture was fixed with SMC in the experimental group and with 4 hole dynamic compression plate （DCP） in the control group. Samples from the fracture gaps were obtained at 3. 7, 14, 21, 28, 56 and 84 day. The contents of PGE2 and cAMP were detected through radioimmunity method and the process and quality of fracture healing was observed histologically. RT-PCR was employed to study the expression of some related genes during endochondral ossification, including type I collagen, type Ⅱ collagen and osteocalcin mRNA. Results： The contents of PGE2 and cAMP were elevated after fracture, which were significantly higher in the experimental group than those in the control group at 3 and 4 weeks postoperatively. In terms of histology and RT-PCR, the mineralization of cartilage matrix, the endochondral bone formation and the callus remodelling took place earlier in the experimental group. Conclusion ： The persistent dynamic longitudinal pressure stress of SMC may contribute to matrix mineralization and endochondral bone formation of callus, leading a promotion of bone healing, which was considered to be closely related with the signaling pathway theft had several critical components including COX 2, PGE2 and cAMP.
出处
《解剖学杂志》
CAS
CSCD
北大核心
2008年第4期570-574,共5页
Chinese Journal of Anatomy
