The effect of exogenous VEGF on bone activity of rabbit heterotopic allograft decalcified bone / 中华显微外科杂志

ABSTRACT

Objective To investigate the effect of exogenous vascular endothelial growth factor (VEGF) on bone activity of rabbit heterotopic allograft decalcified bone.Methods 140 adult healthy China white rabbits were selected,no limitation with sex,20 rabbits as the donor preparation of allogenic decalcified bone,according to the random number table,the rest was divided into the experimental group (allograft decalcified bone ± VEGF) and the control group (Allograft decalcified bone),each group contained 60 rabbits.For the experimental group,the prepared 1.5 cm long homologous decalcified tibia was placed in rabbit right thigh of rectus femoris and vastus medialis muscle gap near by saphenous artery,and fixed on the femur with two 0.8 mm Kirschner wire.In the vicinity of the skin,implanted an osmotic pump which contain the VEGF solution 200 μl with concentration was 0.5 μg/ml.In the control group,implanted the isometric allograft decalcified bone in rabbit right thigh corresponding parts with the same method.Each group respectively at 0,2,4,6,8,10 weeks to death 10 white rabbits,By specimen observation,HE dyeing observation and detection of type Ⅰ glue protein fluorescence intensity,Analysis the bone activation degree of two groups of bone allograft decalcified.Results Experimental allograft decalcified bone gradually wrapped by connective tissue membrane,its surface appear different size of the pits and gradually increased and become deep,while the control group pits relatively little and shallow.In the experimental group and control group,the fluorescence intensity of type Ⅰ collagen reached its peak respectively at 8 weeks (47.57 ±3.50) and 10 weeks (45.07±6.02),with no statistically significant (P ＞ 0.05).Conclusion Rabbit allograft decalcified bone implanted in the muscle clearance with abundant blood supply can be transformed into activated bone after 10 weeks,and after applying exogenous VEGF,allograft decalcified bone can be transformed into activated bone after 8 weeks,the bone activation process obviously speed up.The reaults confirmed the exogenous VEGF can obviously promote the ectopic rabbit bone allograft decalcified bone activation process.