摘要
目的 观察血管化组织工程骨修复兔股骨干骨缺损的成骨特点,初步探讨其修复骨缺损的机制.方法 32只新西兰大白兔均制备左侧股骨干15 mm段性骨缺损模型,随机分为两组,实验组：兔自体骨髓基质干细胞复合β-磷酸三钙（β-TCP）构建组织工程骨同时联合血管柬植入骨缺损;对照组：单纯植入组织工程骨.于术后2、4、8、12周行组织学观察骨形成与改建情况,同时行免疫组织化学,荧光定量聚合酶链反应,免疫印迹检测修复骨段内血管内皮生长因子（VEGF）的表达.结果 组织学观察显示随着时间发展,两组成骨量均逐渐增加,从4周起实验组骨修复优于对照组;实验组各时间点组织工程骨中VEGF的表达量高于对照组,随着时间延长,VEGF呈先增高后降低趋势,在4周时表达量最大.结论 血管化组织工程骨可有效促进兔股骨缺损的修复,植入血管束能促进VEGF的表达,VEGF是促进骨再生和血管再生的重要因子.
Objective To investigate the effectiveness and mechanism of tissue engineering vascularized bone in repairing segmental femoral bone defects in rabbits.Methods,Thirty-two rabbits were randomized into two groups（n=16 each）.A segmental and critical bone defect of 15 mm in length was made at left femur.In experimental group,the tissue engineering bone constructed from autologous bone marrow mesenehymal stem cells plus β-tricalcium phosphate（β-TCP）and vascular bundle was implanted into bony defect.In control group.there was no implantation of vascular bundle.Animals were sacrificed at 2,4,8 and 12 weeks post-implantation respectively.Histological observation was conducted to determine the process of new bone formation and remolding.The expression of vascular endothelial growth factor（VEGF） in new bone was measured by immunohistochemistry,real-time PCR and Western blot.Results As indicated by histological observations over time,new bone formation increased in both groups.It was better in the experimental group than the control group at the beginning of 4 weeks.The expression level of VEGF gradually decreased in each group after an initial rise.And the expression of VEGF was significantly higher than the control group after implantation at all time points and peaked at 4 weeks.Conclusion Tissue engineering vascularized bone accelerates bone repair in critical size defect model of femur in rabbit Implantation of vascular bundle can promote the secretion of VEGF.And VEGF is an essential mediator of both angiogenesis and ossification.
出处
《中华医学杂志》
CAS
CSCD
北大核心
2010年第23期1637-1641,共5页
National Medical Journal of China
基金
国家自然科学基金（30600643）
国家自然科学基金广东省联合重点项目（u0732003）
国家自然科学基金面上项目（30872638）
国家＂973＂重点基础研究发展计划（2009CB930000）
广州医学院青年科研基金（广医科：2010-01）
关键词
生物医学工程
内皮
血管
骨缺损
Biomedical engineering
Endothelium,vascular
Bone defect
