The Experimental Study On Intrinsic Mechanism Of Tendon Healing By Injecting Vascular Endothelial Growth Factor (VEGF) In The Wound Tendon Section Comparing With Basic Fibroblast Growth Factor (bFGF) In A Rabbit Model

Objective:to study the effects of vascular endothelial growth factor (VEGF)on intrinsic mechanism of Achilles tendon healing comparing with basic fibroblast growth factor(bFGF)by using one of them injecting in the tendon section and to analysis the different effects of the both in different stage of tendon healing.Methods:36 rabbits were separated three groups randomly,each group takes 12 rabbits.They were named control group,VEGF group, bFGF group.To cut off the gastrocnemius branch of RT.Achilles tendons set up the tendon injury model and use the silica-gel tube to sever the tendon and the peripheral connective tissue.And then to repair the suture sites in improved Kessler method with 5-0 line.The animals of control group were treated with nothing in the sutured tendon sites;the animals of VEGF group were treated with VEGF 100ng(100ng/0.2ml);the animals of bFGF group were treated with bFGF 100ng(100ng/0.2ml). The animals were treated with the same drug in the tendon section at the time of 7d,14d,21d post-operation.At the time of 2,4,6 weeks post-operation,to evaluate the tendon adhesion between the peripheral tissue and tendon and between the tube and the tendon,to count the quantities of fibroblast and the content of collagen fibril inside the graft location of tendon with histological test,and then analysis the differences among the groups by statistics method.Result:there is no significant difference in tendon adhesion among the three groups at the time of 2,4,6 weeks post-operation (P＞0.05).There are significant differences between the experimental group(VEGF group,bFGF group)and the control group in fibroblast and collagen fibril at the time of 2,4,6 weeks post-operation(P＞0.05).The experimental groups have more fibroblast at 2 weeks post operation and more collagen fibril at every time post operation,but there are significant difference in quantities of fibroblast at 2 weeks post operation between VEGF group and bFGF group(P＜0.05),the group of VEGF have much more fibroblast than the bFGF group.However,the group of bFGF is better in content of collagen fibril at the time of 4 weeks post operation, and have significant difference(P＜0.05);there is no significant in quantities of fibroblast at the time of 4,6 weeks post operation and no significant in collagen fibril at the time of 2,6 weeks post operation(P＞0.05)between the two groups.In each group there are significant differences in fibroblast and collagen fibril at the different times post operation.Conclusion:①vascular endothelial growth factor and basic fibroblast growth factor could promote intrinsic mechanism of tendon healing;②the growth factor of VEGF takes a more important role in fibroblast proliferation than bFGF in the early stage of Achilles tendon healing.But the growth factor of bFGF in producing collagen fibril is better than VEGF in Achilles tendon healing.