[Subcutaneous injection of plasmid VEGF gene: a method of gene therapy to enhance the viability of random skin flap].

OBJECTIVE:Gene therapy has been becoming one of the most attractive medical areas. But the using of gene therapy in plastic surgery is relatively scarce. Our purpose was to investigate the effect of naked plasmid encoding Vascular Endothelial Growth Factor on the viability of the random skin flap by directly injected subcutaneously. METHODS:30 female Sprague-Dawley rats randomly divided into three groups. A random dorsal skin flap of 3 cm x 9 cm was elevated in each of the rats. And 1 ml double-distilled water solution was injected subcutaneously, which was only water in group 1 during the operation, 200 micrograms VEGF cDNA plasmid in group 2 during the operation, 200 micrograms pcDNA3.1/zeo(+)--VEGF in group 3, 24 hours before the operation, respectively. 7 days after the operation, all the animals were sacrificed by overdose anesthetic. The survival tissue was measured with planimetry. Two samples were harvested from each group for pathological check and immunohistochemical test. RESULTS:Immunohistochemical staining demonstrated that there was human VEGF deposited around the capillary in the flaps treated with VEGF gene. The flaps treated with VEGF gene had a larger percentage of survival skin (group 1 = 47% +/- 5.4%, group 2 = 65.4% +/- 6.3%, group 3 = 72.3% +/- 8.5%, P < 0.05). CONCLUSION:VEGF gene directly injected into subcutaneous can express VEGF. It makes the gene therapy simple and practical and will be promising future in the tissue transplantation.