rhBMP-2对兔下颌骨牵引成骨的影响及BMP-4的表达

 目的 通过观察兔下颌骨牵引成骨过程,探讨不同剂量重组人骨形成蛋白2(rhBMP-2)在不同时间对成骨区新骨生成的影响及其BMP-4的表达.方法 日本大耳白兔48只行单侧下颌骨牵引,分别将不同剂量 rhBMP-2胶原复合物植入骨切开处,间歇期5 d,牵引速度0.4 mm/d,2/d,共牵引5 d.用免疫组化方法观察牵引成骨新骨生成区BMP-4在固定1、7、14、28 d时的表达及新骨生成情况.结果 随着稳定期延长,牵引间隙内新骨逐渐生成.1.5 mg BMP-2剂量组的新骨生成优于对照组,3 mg BMP-2剂量组的新骨组织在同一时期内最多.BMP-4主要定位于成骨细胞和软骨细胞中,表达高峰出现在稳定期的1、7 d,此后逐渐下降,第28天阳性表达微弱.结论 rhBMP-2能促进牵引成骨,并具有浓度依赖性,BMP-4可能在牵引成骨的早期发挥重要作用.

Effects of different concentrations of rhBMP-2 on mandibular traction osteogenesis and expression of BMP-4 in rabbits

Objective To study the progress of mandibular osteogenesis （DO） and inverstlgocte the effects of different concentrations of rhBMP- 2 on bone forming and the on expression of BMP - 4 in the different consolidation period of DO. Methods Forty- eight rabbits were under went unilateral mandibular DO, Different concentrations of rhBMP- 2 with collagen cartier was implanted in the osteotomy site of the mandibles, After a latency period of 5 days, the mandibles were lengthened 4 mm at a rate of fraction 0.4 mm/d, twice a day,for 5 eonsecutiue days. Calluses were processed for immunohistochemical study. The expressions of BMP - 4 were observed on days 1,7, 14, 28 of consolidation period, Results The mandibular side treated with 1.5 nag rhBMP - 4 had greater amount of new bone than that treated with collagen sponge, and that treated with 3rag rhBMP - 4 had greatest amount of new bone,The expression of BMP-4 roached the peak on days 1,7,descended on the 14th day,and was rarely seen on the 28th day. BMP- 4 was primarily located in the osteoblasks and cartilage cells. Coudusions rhBMP - 2 accelerates bone formation of mandibular fraction osteogenesis in concentration dependant manner, BMP- 4 may play important role in the early stage of DO.