急性放射性皮肤溃疡发生发展过程中VEGF的表达水平与单纯伤口愈合的对比研究

目的 探讨血管内皮生长因子VEGF在急性放射性皮肤溃疡组织中的表达水平及对溃疡形成、发展、愈合的影响。方法 采用雌性Wistar大鼠,以⁶⁰Co γ射线局部照射法建立急性放射性皮肤溃疡动物模型,并以手术法建立单纯皮肤伤口动物模型,观察病变55 d,采用免疫组化、原位杂交和图像分析等方法检测单纯伤口及皮肤溃疡组织中VEGF的转录和表达水平。结果 照后14 d照射野内开始出现皮肤溃疡,之后逐渐扩大、融合、加深。皮肤受照射区多种细胞,特别是溃疡床表皮细胞、成纤维细胞及血管内皮细胞中VEGF的转录及表达水平均较正常皮肤组织有所增强,但与单纯伤口组比较,溃疡组织中VEGF的转录及表达水平明显降低。结论 辐射诱导的皮肤溃疡组织中VEGF表达水平较单纯伤口组降低可能与溃疡发生、发展及难愈合的分子机制相关。

VEGF Expression during the Formation and Development of Radiation - Induced Skin Ulcers and Its Effects on Ulcer Healing: A Comparative Study with Normal Wound Healing

Objective To study VEGF expression during the formation and development of radiation-induced skin ulcers and its effects on ulcer healing.Methods A rat model which was locally irradiated with ⁶⁰Co γ-rays was used, and another rat model of simple skin wounds was made.Pathological changes were observed for 55 days.Immunohistochemistry, in situ hybridization and image analysis were performed to detect VEGF expression in the tissue of radiation skin ulcers and in the simple wounds.Results Skin ulcers were found on day 14 after irradiation, and they were enlarged and deepened gradually during the observation period.In the irradiated skin, especially in the epidermal cells, fibroblasts and endothelial cells in the ulcer beds, the expression of VEGF was higher than that in normal skin.But VEGF expression was obviously decreased in the radiation ulcer beds compared to that in the surgical wound beds.Conclusion After irradiation, the decreased expression of VEGF may play an important role in the formation, development and nonhealing mechanism of radiation skin ulcers.