心肌内控制释放碱性成纤维细胞生长因子促进血管再生的作用

背景实验研究表明,生长因子能促进心肌血管再生,采用纤维蛋白胶心肌内控制释放碱性成纤维细胞生长因子的血管再生作用和机制尚不明确.目的评价纤维蛋白胶心肌内控制释放碱性成纤维细胞生长因子对急性心肌梗死犬局部相关血管生长因子表达与细胞增殖水平的影响,探讨心肌内控制释放碱性成纤维细胞生长因子对血管再生的治疗作用.设计完全随机分组设计,对照实验.单位首都医科大学附属北京安贞医院心内科、华中科技大学同济医学院附属协和医院心内科和上海新兴血液制品研究所.材料实验于2001-06/2003-03先后在华中科技大学同济医学院附属协和医院外科动物实验室和解放军总医院医学实验动物中心完成.选用清洁级健康成年杂种犬12只,雌雄不拘.随机将犬分为2组激光心肌血运重建组和碱性成纤维细胞生长因子组,每组6只.方法①将12只成年健康杂种犬于麻醉开胸后暴露心脏,结扎左前降支制作急性心肌梗死模型.动物随机分为2组激光心肌血运重建组于急性心肌梗死30 min后行透壁心肌打孔;碱性成纤维细胞生长因子组则于急性心肌梗死30 min后行非透壁心肌打孔,并随后向孔道内注射含有碱性成纤维细胞生长因子的纤维蛋白胶.②术后第8周,采用免疫组织化学染色和HPIAS-2000型彩色病理图文分析系统免疫组织化学分析程序分析缺血心肌局部血管内皮生长因子、转化生长因子β1和增殖细胞核抗原表达水平的变化.③均数间比较采用非配对t检验或方差分析.主要观察指标激光心肌血运重建组和碱性成纤维细胞生长因子组梗死区心肌血管内皮生长因子、转化生长因子β1和增殖细胞核抗原免疫组织化学染色的定量分析.结果激光心肌血运重建组和碱性成纤维细胞生长因子组分别有5只和6只犬进入结果分析,免疫组织化学定量分析发现,碱性成纤维细胞生长因子组梗死区心肌血管内皮生长因子、转化生长因子β1和增殖细胞核抗原染色的显色面积均高于激光心肌血运重建组(t=-7.505,-2.690与-6.895,P＜0.05),碱性成纤维细胞生长因子组增殖细胞核抗原染色的平均吸光度也高于激光心肌血运重建组(t=-5.271,P＜0.05).结论心肌内控制释放碱性成纤维细胞生长因子能提高缺血心肌局部相关血管生长因子(如血管内皮生长因子、转化生长因子β1等)的表达水平,增强细胞增殖,从而促进血管再生.

Enhanced expression of vascular growth factors and cell proliferation by controlled-releasing basic fibroblast growth factors in canine myocardium

BACKGROUND: Experimental evidence suggests that growth factors can promote myocardial angiogenesis, but the effect and mechanism of basic fibroblast growth factor (bFGF) in controlled release delivered via fibrin glue has not been fully recognized.OBJECTIVE: To evaluate the effect of controlled-release bFGF delivered via fibrin glue in the myocardium on the expressions of vascular growth factors and cell proliferation in the local acute myocardial infarct area in canines, and assess the therapeutic effect of this strategy.DESIGN: Completely randomized controlled experiment.SETTING: Department of Cardiology, Beijing Anzhen Hospital, Capital University of Medical Sciences; Department of Cardiology, Union Hospital of Tongji Medical College, Huazhong University of Science and Technology; Shanghai Xinxing Blood Product Research Institute.MATERIALS: This experiment was carried out in the Laboratory of Animal Surgery, Union Hospital of Tongji Medical College, Huazhong University of Science and Technology, and the Experimental Animal Center of Chinese PLA General Hospital between June 2001 And March 2003.Twelve clean healthy adult mongrel dogs of either sex were selected and randomized into transmyocardial laser revascularization group and bFGF group with 6 in each group.METHODS: With appropriate anesthesia, the chest of the dog was opened and the left anterior descending (LAD) branch of the coronary artery was ligated to establish acute myocardial infarction (AMI) model.The dogs were then randomized into transmyocardial laser revascularization group to receive transmural myocardial penetration 30 minutes after AMI and bFGF group with non-transmural myocardial penetration 30 minutes after AMI and subsequent injection of bFGF-containing fibrin glue into the channel. The expressions of vascular epithelial growth factor (VEGF), transforming growth factor beta 1 (TGFβ1) and proliferating cell nuclear antigen (PCNA) in the loacl ischemic myocardium were examined immunohistochemically (IHC) at postoperative 18 weeks.MAIN OUTCOME MEASURES: Quantitative IHC analysis of VEGF,TGFβ1 and the PCNA expressions in the local ischemic myocardia in transmyocardial laser revascularization group and bFGF group.RESULTS: Five dogs in the transmyocardial laser revascularization group and 6 in the bFGF group survived the operations. Quantitative IHC analysis revealed obviously larger positive area stained for myocardial VEGF,TGFβ1 and PCNA in bFGF group than in transmyocardial laser revascularization group (t=-7.505, -2.690 and -6.895, P ＜ 0.05), and the average absorbance of PCNA staining in bFGF group was greater than that in the transmyocardial laser revascularization group (t= -5.271, P ＜ 0.05).CONCLUSION: Controlled-releasing bFGF delivered in the myocardium can increase local expressions of the vascular growth factors in the ischemic myocardium and enhance cell proliferation, promoting revascularization after AMI.