Effect of Vascular Endothelial Growth Factor on Skin Graft Survival in Sprague-Dawley Rats

Abstract

To examine the effect of exogenous vascular endothelial growth factor (VEGF) on skin graft survival in Sprague-Dawley rats. Dorsal full-thickness skin grafts were harvested from 18 Sprague-Dawley rats. To simulate human full-thickness skin grafts, the panniculus carnosus muscle was removed from the undersurface of each graft. The recipient beds were delivered subfascial injections of recombinant human VEGF or isotonic sodium chloride solution in 12 animals before replacement of the grafts (6 in each group). Grafts were replaced without injections in 6 sham control animals. Using planimetry, grafts were analyzed for necrosis along epidermal and dermal surfaces on postoperative day 7. Results were compared between groups. To determine the role of the panniculus carnosus muscle in graft survival, 12 Sprague-Dawley rats underwent the same procedure with an intact panniculus carnosus muscle and with subfascial injections of VEGF or physiologic isotonic sodium chloride solution (6 in each group). Analyses were performed on postoperative day 14. The mean microvascular density was determined in each graft after staining with anti-factor VIII antibody. The mean percentage of dermal necrosis in VEGF-treated skin grafts (10.0%) was significantly lower than that in saline-treated grafts (26.7%) or in control grafts (18.9%). Reduced, but not significant, epidermal necrosis was found in VEGF-treated rats vs saline-treated rats. No difference was found in VEGF-treated grafts vs saline-treated grafts when the panniculus carnosus muscle was left intact. Increased microvascular density was observed in VEGF-treated grafts vs saline-treated grafts, which did not reach statistical significance (P = .17). Exogenously administered VEGF may improve the outcome of full-thickness skin grafts by decreasing dermal necrosis.