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Objective: To establish rabbit mandibular distraction bone and periosteal distraction osteogenesis model based on in situ hybridization method to detect hepatocyte growth factor (hepatocyte growth factor, HGF) expression pattern, to explore the role of HGF play The mechanism of action, in order to the factor exogenous application of gene therapy to accelerate bone formation to provide a theoretical basis. Methods: 56 adult New Zealand rabbits were bone experimental animals were divided into the Distraction group and the fracture group (n = 20), the stretch group line both sides of the mandible distraction osteogenesis with periosteal distraction osteogenesis, distraction incision, seven days after intermission 0.5mm/12h speed stretch 7d after fixed delay period, stretch to the end of the period, the fixed period 1w, 3w, 5w, four animals were sacrificed at the end; fracture group does not pull Zhang, after 1w, 2w, 3w, 5w, 7w end of four animals were sacrificed. Periosteal distraction bone experiments on the the rabbits side of the body of the mandible periosteum stretch after the 8d stretch twice, each 1mm, start from 9d per 4d stretch 1mm for 20d, the other side as a blank control side, respectively, after 28d, 35d, 42d, 56d four animals were killed. Remove mandible specimens, histological analysis of the specimens by HE staining and in situ hybridization and detection of hepatocyte growth factor expression pattern. Results: distraction osteogenesis stretch group delay period distraction gap filled fibroblasts and collagen fibers, visible inflammatory cells scattered in between the fibers, stretch ending visible a small amount of new trabecular bone and osteoid along the traction direction formed fixed 5w visible when a large number of bone tissue formation, reduced fibrous tissue. HGF mRNA little expression in the intermittent period, mainly located in the cytoplasm of inflammatory cells in the distraction gap, the distraction the end of the visible positive staining mainly located in the distraction gap vascular endothelial cells and vascular intramural charge interstitial cells, bone fragments new bone forming regions began to appear positive staining, fixed 1w weeks, the positive expression intensity peak, with time, the positive expression intensity, fixed 5w, basic testing positive expression of its purpose, the stretch group and fracture group There was no significant difference. Periosteal distraction bone experiments postoperative 28d stretch the side of the periosteum and cortical contact parts began to appear the cell hyperplasia active, periosteum and bone contact with parts of the cell volume increases, bone matrix deposition, part of the bone matrix surrounding cells; surgery After 42d visible trabecular structure parallel to the stretch direction, the postoperative the 56d newborn bone more mature, trabecular thickening increased. Weakly positive expression of HGF mRNA in the normal periosteum only in a small number of mesenchymal cells in the stretch by the external force, increased expression after 35d when visible positive expression in the new bone matrix, with time expression decreased gradually, to postoperative 56d, with expression levels close to normal periosteum. Conclusion: hepatocyte growth factor in the formation process of distraction osteogenesis with periosteal distraction osteogenesis organization positive expression which mesenchymal cells and vascular wall cells express HGF mRNA longer positive staining is also strong, these cell synthesis of endogenous HGF may be on cell proliferation, differentiation and tissue formation has a role in promoting. The experimental results by the method of gene therapy application HGF promotes distraction osteogenesis provide experimental basis.
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