大鼠急性放射性皮肤溃疡愈合过程中血小板衍生生长因子B及其受体的表达

The expression of platelet-derived growth factor-B and its receptor b in acute radiation-induced skin ulcers in rats

目的：观察血小板衍生生长因子(PDGF)-B及其受体(在急性放射性皮肤溃疡愈合过程中的动态表达,探讨急性放射性皮肤溃疡难愈合的机理。方法：应用50Gy^(60)Coγ射线单次照射大鼠制作急性放射性皮肤溃疡致伤模型,并制作皮肤全层切割伤模型作为对照；采用免疫组织化学及原位杂交等方法,动态观察大鼠急性放射性皮肤溃疡及皮肤全层切割伤创面内PDGF-B及其受体β的表达。结果：与皮肤全层切割伤比较,照射后14～28d,急性放射性皮肤溃疡内PDGF-B及其受体β的表达明显减弱；照射后35～55d,表达进一步减弱。结论：急性放射性皮肤溃疡内PDGF-B及其受体β的表达减弱可能是急性放射性皮肤溃疡难愈合的机理之一。

Objective:To investigate the expression of platelet-derived growth factor-B(PDGF-B) and its receptorβ(PDGFR-b) in acute radiation-induced skin ulcers,and to explore the mechanism of refractoriness of radiation- induced skin ulcers.Methods:A model of acute radiation-induced skin ulcers in rats was replicated with 50Gy 60Coγirradiation,with a group of controls with full-thickness skin excision wounds.The expression of PDGF-B and PDGFR-b were assessed by histochemical and in situ hybridization technics.Results:Compared with full- thickness skin excision wounds,the expression of PDGF-B and PDGFR-b were reduced in radiation-induced skin ulcers 14～28 days after radiation,and they were still reduced gradually 35～55 days after radiation.Conclusion: The reduction of PDGF-B and PDGFR-b might be one of the mechanism of refractoriness in healing of acute radia- tion-induced skin ulcers.