大鼠缺血下肢微血管生成与运动训练

背景:研究表明缺血可通过侧支循环的建立和血管的新生得到代偿,运动训练可以改善患者缺血下肢血液供应,但运动是否能够促进侧支循环的建立至今少有报道.目的:探讨运动训练促进大鼠缺血下肢微血管生成的机制.方法:将SD大鼠随机分为运动训练组、模型组和假手术组.除假手术组外,其余组均建立大鼠左下肢缺血模型.建模1周后运动训练组大鼠跑步训练30 min/d.模型组和假手术组均为日常活动.运动训练4周后取各组大鼠大腿内收肌组织块免疫组化检测微血管密度、血管内皮生长因子和碱性成纤维细胞生长因子的表达,同时取骨髓内皮祖细胞,检测其成血管生成能力.结果与结论:运动训练组内皮祖细胞、大鼠肌组织血管内皮生长因子、碱性成纤维细胞生长因子的表达和微血管密度均高于模型组和假手术组(P<0.01).运动组骨髓内皮祖细胞的体外血管生成能力比假手术组及模型组增加(P<0.05).结果提示下肢缺血刺激可以促进微血管新生,而运动训练可以增强该效应.

Effects of exercise training on microangiogenesis of rat ischemic lower limbs

BACKGROUND:Previous studies demonstrated that ischemia can be compensated by establishing collateral circulation and microangiogenesis,and exercise training can ameliorate blood supply of ischemic lower limb.However,whether exercise training accelerate establishment of collateral circulation remains poorly understood.OBJECTIVE:To explore the mechanism of exercise training on accelerating microangiogenesis of rat ischemic lower limb.METHODS:Sprague-Dawley rats were randomly divided into the exercise training,model and sham-surgery groups.All animals were established left lower limb ischemia models except those in the sham-surgery group.Rats in the exercise training group were forced running 30 minutes per day at 1 week after model preparation and those in other groups were performed daily activities.The adductor of ischemic lower limb was obtained for the examination of microvessel density and the expressions of vascular endothelial growth factor and basic fibroblast growth factor.Simultaneously,bone marrow-derived endothelial progenitor cells were harvested for detection of microangiogenesis.RESULTS AND CONCLUSION:Number of endothelial progenitor calls,expressions of vascular endothelial growth factor and basic fibroblast growth factor,as well as microvessel density of the exercise training group was obviously greater than those in the model and sham-surgery groups(P<0.01).Compared with the model and sham-surgery groups,in vitro vasculogenesisof bone marrow-derived endothelial progenitor cells in the exercise training group was increased(P<0.05).These findings demonstrated that lower limb ischemia increases microangiogenesis,and exercise training enhances this effect.