Study On Changes Of Vascular Endothelial Cell Growth Factor(VEGF) And Angiopoietin-1(Ang-1) Expression During Wound Healing Of The Wound And The Radiation Skin Burn

Object: Radiation skin burn is a kind of injury which is refractory to healing. The expression of the cytokines reduced in radiation skin burn compare with the normal wound, but there is no report about the change of vascular endothelial cell growth factor (VEGF) and angiopoietin-1 (Ang-1) expression in radiation skin burn. Thus, we study the dynamic changes of vascular endothelial cell growth factor (VEGF) and angiopoietin-1 (Ang-1) expression in normal and radiation skin burn during wound healing, and provide significant experimental data which is helpful for the further research on the mechanism and therapy of the wound healing caused by radiation.Methods: In this study, 57 SD rats were divided into two groups:wound group(24 rats) and radiation burn group(33 rats). In radiation burn model, we irradiated the haunch skin of SD rats by using electron rays,take the specimens at different time . In the full-thickness incision model, we made the wound on the dorsal skin, and take the specimens at different time. In both models, three normal rats were taken randomly as the control group. The pathomorphology changes of the wound were observed through the HE staining, and we also observed the dynamic changes of VEGF and Ang-1 expression in thenormal wound and radiation burn through the SP immunohistochemical techniques and western blot . By using these methods, we could make a further study on the effects of the two cytokines in capillary regeneration.Results: In normal wound model, the changes of the expression of VEGF and Ang-1 protein were substantial coincidence. The level began to increase at 1st after wound, and reached the peak from 5th to 7th , then decreased gradually to the normal level after 7th. But in radiation skin burn,the changes of their expression were discrepancy. The expression of VEGF protein was low for a long time after radiation, and reached the lowest level at 11th, then it became gradually increase. The expression of Ang-1 protein began to increase at 1st after radiation, and reached the peak at 14th , then gradually decreased.