Aplication Of Collagen Scaffolds Loaded With CBD-VEGF For The Rat After Spinal Cord Transaction

Objective: To investigate the effects of the collagen scaffolds combined with vascular endothelial growth factors(VEGF) on the neural recovery after SCI, by implanting CS/CBD-VEGF into the model rats of full-cut spinal cord. Methods: 80 male rats were randomly divided into four groups: sham-operate d group, control group, CS-treated group and CS/CBD-VEGF group, each group included 20 rats. The model of a T9 full-cut spinal cord was made in all groups but sham-operated group. After operation,the Basso-Beattie-Bresnahan(BBB) score was graded for each group at 1 week intervals for 12 weeks. At the forth, tenth and twelfth weeks,the spinal cord sections were evaluated by histology and immunohistochemistry. The wet weight of gastrocnemius muscle were measured, and Masson’s trichrome staining was performed on both sides at 10 and 12 weeks post injury. Results: All of the animals underwent successful surgery, none of them were excluded from the experiment. After a 4 weeks’ evaluation,we found that the CS/CBD-VEGF group had a higher survival rate than other two groups. From the seventh week to twelfth week, the BBB scores in the CS/CBD-VEGF group were significantly higher than that in the CS group and control group(p≤0.05).After 10 weeks, the difference of BBB scores between CS group and control group increased gradually(p≤0.05).By immunohistochemistry, the CS/CBD-VEGF group performed higher CD34-positive endothelial cells density and NF-positive neural fiber density, but lower GFAP-positive fibroblast density than other groups at 4,10 and 12 weeks after surgery.According to the measurement of gastrocnemius muscle at 10 and 12 weeks after surgery, we known that the CS/CBD-VEGF group had a higher wet weight of gastrocnemius muscle and percentage of muscle-positive area in transverse sections than the CS group and control group. Conclusions: The study indicates that transplantation of CS/CBD-VEGF into the model rats of full-cut spinal cord can improve the micro environment,guide axon growth and promote neovascularization at the injury site. It is benefit for the function recovery and can arise the survival rate. Therefore, CS/CBD-VEGF transplantation might be a promising method for SCI treatment in clinical.