【摘要】 目的　研究重组人VEGF基因对大鼠缺血TRAM皮瓣成活的影响 ,探讨基因治疗缺血皮瓣的可能性及疗效。方法　动物实验分 4组 ,实验组每只皮下注射PcDNA3 1VEGF 5 0 0 μg ;阳性对照组每只注射VEGF 10 0ng;空白对照组每只注射生理盐水 1ml;阴性对照组每只注射PcDNA3 15 0 0μg。用ELLSA法及免疫组化法测定VEGF基因表达水平 ,测定皮瓣成活面积及皮下组织中微血管密度 ,观察该基因对皮瓣成活的影响。结果　实验组皮瓣成活面积及切片微血管密度显著高于阴性对照组及空白对照组 (P <0 0 5 ) ,与阳性对照组差异无显著性意义 (P >0 0 5 )。免疫组化显示实验组中有大量棕褐色抗原抗体复合物沉积在小血管内皮细胞胞浆内。结论　直接皮下注射PcDNA3 1VEGF ,可在注射部位表达具生物活性的VEGF ,促进皮下微血管形成 ,提高缺血TRAM皮瓣的成活面积。更多还原

【Abstract】 Objective To establish a stable ischemic TRAM flap model in rats and observe the effects of rhVEGF gene on the ischemic flap. Methods Materials were administrated via subcutaneous injection 5 days before the TRAM flap procedure.32 animals were divided into four groups.The first group was treated with PcDNA3 ^1VEGF;the second group with PcDNA3 ^1 as the negative control;the third group with normal saline as the frank control,and the fourth group with VEGF as the positive control.The material was given while the procedures were performed.The serum levels of VEGF before and after the operation were measured with ELLSA kit.The flap was harvested for immunohistological evidence of VEGF protein expression.The viable area of the flap was calculated with AutoCAD software.The microvessel density(MVD) of the subcutaneous tissue of the flap was counted. Results The average viable area of the TRAM flap in model animals was (3 ^61±1 ^06) cm +2[(16 ^04±4 ^71)%].Comparing the mean viable area of the flap in the PcDNA3 ^1VEGF group[(7 ^98±2 ^64) cm +2] with that in the normal saline group [(4 ^13±1 ^77) cm +2],the difference was significant( P <0 ^05).There was no significant difference between the PcDNA3 ^1VEGF group and the VEGF group[(7 ^31±1.22)cm +2] in terms of mean viable flap area.The difference of mean MVD values between the PcDNA3 ^1VEGF group and the negative control group was significant( P <0.05),but was not significant between the gene treatment group and the positive control group.The serum level of VEGF did not increase significantly up to 9 days after the administration of PcDNA3 ^1VEGF( P >0 ^05).Immunohistochemical staining documented the increased deposition of VEGF protein in the plasma of endothelial cells of the flap that was injected with PcDNA3 ^1VEGF. Conclusion The unilateral inferior-pedicled TRAM flap as an ischemic flap model is stable and suitable for statistic treatment.Subcutaneous injection of rhVEGF gene can express biologically active VEGF at the site,increase MVD and the viable area of the TRAM flap.更多还原