OBJECTIVETo evaluate the effect of local application of vascular endothelial growth factor (VEGF) via adenovirus-mediated gene transfer on survival of full thickness flaps selected randomly in rats.

METHODSThirty Sprague-Dawley rats weighing 480-520 g were used in this study. A dorsal flap (8 cm x 2 cm) in full thickness with the pedicle located at the level of the iliac crest was designed. Then the rats received 1,012 pfu replication-deficient recombinant adenovirus carrying VEGF (AdCMV-VEGF group, n=10), 1,012 pfu recombinant beta-galactosidase adenovirus (AdCMV-Gal group, n=10) and 1 ml saline (saline group, n=10), respectively, in the distal two thirds of the proposed flap by means of subdermal injection at 8 different locations. Three days after treatment, the flaps were elevated as originally designed and sutured back in situ. The survival rate of the flaps was evaluated on day 7 after operation.

RESULTSThe survival rate of the flaps in the AdCMV-VEGF group increased significantly as compared with those of the AdCMV-Gal group (P<0.01) and the saline group (P<0.01). Immunohistochemical staining showed that VEGF was expressed in the survival flaps injected with AdCMV-VEGF. Histological analysis showed that more granulation tissues and angiogenesis were observed in the AdCMV-VEGF group than those in the AdCMV-Gal and the saline groups.

CONCLUSIONSLocal application of adenovirus-mediated VEGF165 cDNA may efficiently improve the survival of ischemic skin flaps.