Establishment and application of rat model of acute β-irradiated skin injury

Objective To establish an experimental rat model of acute β-irradiated skin injury and to study the effects of superoxide dismutase (SOD) on wound healing. Methods Areas of buttock skin (20 mm×40 mm) of 40 male SD rats were irradiated with 45 Gy β-rays generated by linear accelerator, and then the forty rats were divided into two groups randomly: treatment group administrated with SOD (n=20) and control group administrated with normal saline (NS) (n=20). The wound healing time and rate were observed. The pathological changes were observed by light microscopy. The expressions of VEGF (vascular endothelial growth factor) and bFGF (basic fibroblast growth factor) were determined by SP immunohistochemical method. Results The deep second-degree burns was observed following 45 Gy irradiation. The wound healing time in treatment group was shorter than that of the control group (P0.05). Strongly positive (+++) expression of VEGF、 bFGF in treatment group and positive ( ++ ) expression of VEGF、bFGF in the control group were observed 6 weeks, 7 weeks and 8 weeks after the irradiation, while only weakly positive (+) expressions of VEGF and bFGF in both groups 4 weeks, 5 weeks and 9 weeks after the irradiation. Conclusions The wound model of acute β-irradiated skin injury in rat was established and used in study of the effect of medicine on wound healing. SOD can promote the wound healing of acute β-irradiated skin injury.;