超声破坏微泡造影剂促进大鼠心肌血管新生的实验研究

目的探讨超声破坏微泡刺激大鼠心肌内源性VEGF分泌、促进血管生成的新途径。方法正常成年Wistar大鼠30只随机分为3组。第1组超声破坏微泡组，第2组单纯超声辐照组，第3组对照组。每组均进行3次处理。第一次处理3d后每组各取1只大鼠断颈处死后取其心肌，常规HE染色光镜观察心肌结构变化。剩余大鼠于2周后取材，免疫组化检测心肌组织中VEGF表达，CD34免疫组化检测评定超声破坏微泡促进心肌血管新生疗效。结果超声破坏微泡组心肌组织中见大量VEGF和CD34表达，新生血管较多。单纯超声组心肌组织中有较少VEGF和CD34表达，新生血管较少。对照组仅有极少量VEGF和CD34表达，未见明显新生血管。结论超声破坏微泡可刺激心肌内源性VEGF分泌，促进血管新生。

Stimulation of Myocardial Angiogenesis by Ultrasound-mediated Microbubble Destruction in Rats

Objective To investigate whether ultrasound-mediated microbubble destruction can stimulate secretion of vascular endothelial growth factor(VEGF) and angiogenesis in rat myocardium.Methods A total of 30 normal Wistar rats were randomly devided into 3 groups:in group 1,the myocardium was exposed to ultrasound after intravenous injection of microbubbles of 1.0 ml;in group 2,ultrasound was simply used in the myocardium;only was normal saline infused in the control group.Each group was treated 3 times.Thres days after the first experiment,in each group 3 rats were killed and the myocardium were harvested for HE staining to observe the tissue microstructures.The other 27 rats were killed 2 weeks later.Immunohistochemistry stain was used to detect the vascularization.Results There was significant VEGF and CD34 expression in group 1;less in group 2 and little expression in the control.Conclusions Ultrasound-mediated microbubble destruction can facilitate the endogenous secretion of VEGF and accelerate the vascularization in the rat myocardium.