| It,s a common injury of tendon broken and defection in hand surgery. Tendon adhesions, which happened after operative repair or transplantation, restrict tendon to glide and severely prevent the rehabilitation of hand function. Tenolysis is needed subsequently in many times. It has been shown that many growth factors play important role in tendon repair regulation in recent researches. In tendon healing process, tenocytes proliferate and differentiate, synthesize and excrete extracellular matrix such as collegan and fibronectin with the effect of intrinsic growth factors. The growth factors is in action mainly through paracrine or autocrine in local.Intrinsic and extrinsic healing are both existed in tendon healing. the intrinsic healing, the selfrepair by tendon superfacial cells in the nutrien of synovial fluid, can avoid to form adhesions. While the extrinsic healing which is depended on the blood supplies and repair cells origined from the peritendon tissue adhesions, is thought to be the main cause of tendon adhesion formation. Vascular endothelial growth factor(VEGF), the most potent angiogenic factor that has been known, takes important actions in tissue healing and regeneration. It's generally thought VEGF is the main regulation cytokine of increased vascular permeability and angiogenesis in wound environment, and has something to do with the formation of granulation tissue.VEGF is not found in normal adult tendon, after tendon injury, tenocytes not only synthesize extracellular matrix , but also synthesize and excrete VEGF to induce angiogenesis. Angiogenesis accelerate the process of tendon healing,on the other hand it's a latent factor to adhesion. Therefore VEGF may take great actions in tendon extrinsic healing.Neutralizing antibody to VEGF can combine with the active site of VEGF especially and block the binding of VEGF to its receptors. It's supposed that application of appropriate dose of neutralizing antibody to VEGF may decrease the expression of VEGF, consequently restrain the excessive proliferation of granulation tissue, inhibit the extrinsic healing of the tendon, achieve the purpose of preventing tendon adhesion formation.Our research applied the rabbit's flexor digitorum profundus tendon injury model. The flexor digitorum profundus tendon of New Zealand white rabbit in zoneâ…¡was completely transected and immediately repaired using the improved Kessler technique. Immunochemistry and semiquantitative method by computer image analysis systerm were used to determine the expression changes of VEGF and its receptors during tendon healing. The ultrastructure of cells was observed by transmission electron microscope technique. Moreover neutralizing antibody to VEGF was applied to local injury enviroment in order to evaluate its influence on the expression of VEGF, tendon healing, biomechanics and collagen synthesis. All of the above were in purpose of determining the effects of VEGF and its antibody in tendon healing and adhesion, hoping to find out a new clinical treatment method to prevent postoperative tendon adhesion.Results: 1.VEGF and its receptors expression was upregulated after tendon injury in repair site. The expression steped up gradually at 4 days post-operatively, with peak levels seen at post-operative days 7 and 10, then descended. The expression level returned to baseline by day 14. 2. After neutralizing antibody to VEGF was given, expression level of VEGF was decreased in all intervals. Tendon adhesion grade score and tendon gliding were distinctly improved, but it had no influence on collagen synthesis and tendon broken load.Conclusions:VEGF and its receptors were not expressed in normal tendon. The expression level of which increased distinctly in tendon post-injury. VEGF accelerates the process of tendon healing; on the other hand it leads to excessive proliferation of granulation tissue, which results in tendon adhesion formation.2. Application of neutralizing antibody to VEGF in local, it can decrease the VEGF expression level, restrain excessive pr...
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