腺病毒载体介导的VEGF_(165)基因治疗大鼠缺血皮瓣的实验研究

The effect of adenover-mediated VEGF_(165) gene on the survival of random skin flap in rats

目的 探讨局部应用以腺病毒为载体的血管内皮生长因子（Ad-VEGF165）基因治疗对大鼠缺血皮瓣生存的影响.方法 选用SD大鼠30只,体重350～400 g,随机分成3组,每组10只,在其背部形成8 cm×2 cm的全厚随意型皮瓣.于皮瓣远端皮下分别注射携带血管内皮生长因子基因的腺病毒（Ad-VEGF165目的基因组,简称VEGF165组）,携带绿色荧光蛋白基因的腺病毒（Ad-GFP基因组对照,简称GFP组）,磷酸盐缓冲液（PBS空白对照组,简称PBS组）,48 h后按原设计掀起皮瓣并原位缝合,术后7天,测量皮瓣的成活面积,计算成活面积百分比,并采集成活皮瓣组织行免疫组化、组织学检查等.结果 皮瓣成活面积百分比：VEGF165组为（69.4±1.3）%,GFP组为（52.2±1.7）%,PBS组为（52.9±2.9）%,VEGF165组皮瓣成活面积百分比明显高于GFP组和PBS组（P＜0.01）.免疫组化显示VEGF165组毛细血管周围VEGF沉积,组织切片微血管密度明显高于GFP组和PBS组（P＜0.01）.结论 局部皮下注射Ad-VEGF165可诱导局部VEGF蛋白表达,促进新生血管的形成,提高缺血皮瓣的成活面积,是一种简单有效的基因治疗方法.

Objective To investigate the effect of adenovirus- mediated gene therapy of vascular endothelial growth factor （VEGF165） delivered into the subcutaneous space to treat experimental skin flaps in rats. Methods Thirty Sprngue - Dawley rats weighing 350 - 400 g were randomly divided into three groups of ten rats each to form pedided flap （8 cm × 2 cm） of fidl thickness dorsal to the iliac crest. The rats were pretreated by giving subcutaneous injections of adenovirus encoding VEGF165 （Ad - VEGF. 165 ） in treatment group, green fluorescent protein （Ad - GFP） in treatment control group, and PBS in blank control group. Two days after the treatment, a flap was elevated at the designated site and sutured back to its bed. The flap was evaluated for survival rate and processed for histologies on day seven after operation. Results The survival rate of the flap in VEGF165 group was increased significantly, as compared with those in GFP group and PBS group （P 〈 0.01 ）. Immunohistochemical staining showed that VEGF was expressed in the survival flap adjacent to the site of Ad - VEGF165 injection. Histological analysis showed that the was more granular tissue and angiogenesis in the VEGF165 treatment group than in the GFP and PBS control groups. Conclusion Local application of adenovirus - mediated VEGF cDNA may efficiently improve the survival of ischemic skin flap.