心肌内注射腺病毒介导血管内皮生长因子基因的血管生成实验研究

The study of angiogenesis by intramyocardial delivery of recombinant adenovirus vector encoding vascular endothelial growth factor 165 in a pig model of chronic myocardial ischemia

目的 探讨血管内皮生长因子 16 5 (VEGF165)基因的血管生成作用。 方法 在猪冠状动脉回旋支起始处放置Ameroid闭合器 ,制备慢性心肌缺血模型 ,2 8d时行选择性冠状动脉造影 ,观察回旋支狭窄程度。开胸 ,治疗组 ( 6只 )在缺血区心肌内多点注射含人VEGF165基因的重组腺病毒载体 (Ad VEGF165) ;对照组 ( 6只 )在缺血区心肌内多点注射含细菌半乳糖苷酶基因的重组腺病毒载体 (Ad β gal)。转染重组腺病毒载体 2 8d时重复行冠状动脉造影后 ,处死猪 ,取缺血区心肌 ,做组织学检查 ;应用酶标法检测血浆中VEGF浓度 ,采用Rentrop分级、缺血区心肌侧支血管积分和心肌碱性磷酸酶染色法评价血管生成作用。 结果 与对照组比较 ,基因转染 3d时治疗组血浆VEGF增高〔( 114 6± 5 4 ) pg/ml对 ( 6 0 3± 1 8) pg/ml,P <0 0 0 1〕 ,7d时血浆VEGF为 ( 12 8 4± 3 0 ) pg/ml对 ( 70 9± 5 3) pg/ml,P <0 0 0 1,14d后恢复到基线水平。与对照组比较 ,基因转染 2 8d时治疗组Rentrop分级增高 ( 2 8± 0 4对 1 3± 0 8,P <0 0 0 1) ,侧支血管积分增高 ( 4 8± 0 8对 1 7± 0 8,P<0 0 0 1) ,缺血区毛细血管密度增高 ( 2 10± 19对 6 2± 6 ,P <0 0 0 1)。 结论 心肌转染Ad VEGF165后 ,缺血心肌表达VEGF ,产生?

Objective To investigate the effects of angiogenesis with vascular endothelial growth factor 165 gene in a pig model of chronic myocardial ischemia. Methods A recombinant adenovirus vector encoding human vascular endothelial growth factor 165 (Ad VEGF 165 ) was constructed. Plastic ameroid occludors were placed on the proximal left circumflex artery in pig through left lateral fourth intercostals thoracotomy. Ad VEGF 165 was directly injected into the chronic ischemic myocardium in a treatment group (n = 6) and Ad β gal in a control group (n = 6) at 28 days after model was made. The level of VEGF in plasma was measured by ELISA. Coronary angiography was performed at 28 days after ameroid placement and at 28 days after gene transfer. Alkaline phosphatase staining was performed at 28 days after gene transfer. Results Compared treatment group with control group at 3 days after gene transfer, the level of VEGF in plasma was significantly elevated 〔(114 6±5 4) pg/ml vs (60 3±1 8) pg/ml, P <0 001〕, the highest expression was at 7 days later 〔(128 4±3 0) pg/ml vs (70 9±5 3) pg/ml, P <0 001〕 and recovered to baseline 14 days later. Compared treatment group with control group at 28 days after gene transfer, the Rentrop scoring was increased (2 8±0 4 vs 1 3±0 8, P <0 001), collateral vessel development assessed by angiography was increased (4 8±0 8 vs 1 7±0 8, P < 0 001), the capillary vessel density was increased (210±19 vs 62±6, P <0 001). Conclusions VEGF is expressed in ischemic myocardium and induces collateral vessel development in vivo.