摘要
目的探讨急性心肌梗塞后bFGF对缺血心肌血管生成的作用。方法24只健康杂种犬随机分成对照组和实验组,每组观察4个不同时间点,在术后3h内和动物处死前分别采用敏感编码(SENSE)技术行MR电影和心肌灌注MR成像;电镜观察心肌超微结构变化和新生血管生长情况;免疫组织化学方法检测微血管数量。结果实验组左心室射血分数自第10天明显增加;梗死心肌首过灌注呈低强化,延迟扫描信号强度高于正常心肌,曲线上升时间、峰值时间、曲线上升斜率、对比增强率低于正常心肌,第17天时心梗范围显著变小;实验组微血管生长活跃,微血管数量除第1天外余各个时间点实验组均比对照组明显增多;结论心肌内注射碱性成纤维生长因子增加了急性心梗新生血管密度、减小了心梗范围、提高了左心室功能。
Objective To study the effect of intramyocardial administrationof basic fibroblast growth factor on angiogenesis of infarct myocardium indogs. Methods Twenty-four mongrel dogs were randomized into controlgroup and therapeutic group. Acute myocardial infarction was induced byligation of the left anterior descending coronary artery distal to its firstdiagonal branch. As soon as coronary artery was occlused, 50mg of basicfibroblast growth factor in 15ml of saline was injected into the infarct andborder zone in therapeutic group dogs, whereas 15ml saline alone was usedin the same way in control dogs. Every 3 dogs in each group was studied on1st day,3rd day,10th day and 17th day respectively. Electron microscopewas used to observe the growth of capillaries. Angiogenesis was evaluated byimmunohistochemical studies with Ⅷ factor. With sensitivity encoded technique,cine MR and MR perfusion imaging were performed on each dog within 3hours after surgery and before euthanasia to evaluate cardiac function and thecharacteristics of myocardial perfusion. Results In therapeutic group, LVEFimproved markedly since the 10th day. Hypoenhancement on first pass andhyperenhancement on delayed phase appeared in infarct myocardium. Therewere significant differences of the time of upslope, the upslope, peak time ofsignal intensity-time curves and contrast enhancement ratio between infarct andnormal myocardium. The size of infarct myocardium was markedly decreasedon the 17th day. The capillaries grew actively in therapeutic group andmicrovessel density was higher in therapeutic group than in control groupexcept the first day. Conclusion Intramyocardial administration of basicfibroblast growth factor is helpful to increase the growth of microvessels andangiogenesis of infarct myocardium and decrease the size of the infarctmyocardium after acute myocardial infarction.[
出处
《中国CT和MRI杂志》
2003年第1期27-30,34,共5页
Chinese Journal of CT and MRI
基金
国家自然科学基金项目(项目编号:39970227)
