碱性成纤维生长因子对急性心肌梗死血管生成和碱性成纤维生长因子及血管内皮生长因子表达的作用

The effect of basic fibroblast growth factor on angiogenesis and on the expression of basic fibroblast growth factor and vascular endothelial growth factor in acute infarcted myocardium

目的 探讨心肌内注射碱性成纤维生长因子 (bFGF)对急性心肌梗死 (MI)血管生成和bFGF、血管内皮生长因子 (VEGF)表达的作用。方法 2 4只犬建立急性MI模型后随机分成对照组(MI区注射生理盐水 1 5ml)和实验组 (MI区注射 5 0mgbFGF与生理盐水的混合液 1 5ml)。每组观察 4个不同的时间点 (术后第 1天、第 3天、第 1 0天、第 1 7天 )。各组分别在处死前应用敏感编码技术行磁共振电影成像。免疫组织化学方法检测各组心肌细胞中bFGF和VEGF的表达及微血管数量。结果 实验组左心室射血分数自第 1 0天明显增加 ;除第 1天外各个时间点的微血管数量实验组比对照组明显增多 ;心肌缺血区对照组bFGF和VEGF的表达增多。

Objective To evaluate the effect of intramyocardial administration of basic fibroblast growth factor (bFGF) on the angiogenesis and on the expression of bFGF and vascular endothelial growth facotr (VEGF) in infarcted myocardium. Methods Twenty four mongrel dogs were randomized into control group and therapeutic group. Acute myocardial infarction was made by ligation of the left anterior descending coronary artery distal to its first diagonal branch. After coronary artery was occlused,50 micrograms of basic fibroblast growth factor in 15 ml of normal saline were injected into the infarcted myocardium and its border zone in therapeutic group, whereas the same volume of normal saline alone was used in control dogs.Every 3 dogs in each group was studied on the 1st day,the 3rd day ,the 10th day and the 17th day after surgery respectively. With sensitivity encoded technique,cine MR was performed on each dog before euthanasia to evaluate the cardiac function. Angiogenesis and the expression of VEGF and bFGF were evaluated by immunohistochemical studies with factor Ⅷ and the antibodies of VEGF and bFGF. Results In therapeutic group, left ventricular ejection fraction, improved markedly since the 10th day after injection of bFGF. Microvessel density was higher in the therapeutic group than in the control group except on the first day. VEGF and bFGF expressed more in the therapeutic group. Conclusion Intramyocardial administration of bFGF is useful in increasing the growth of microvessels and improving the left ventricular function in acute myocardial infarction.