摘要
Objectives Little is known about the mechanism of exercise-induced angiogenic response in ischemic myocardium. This study was designed to investigate the effects of exercise training on expression of vascular endothelial growth factor and angiogenesis in infarcted heart. Methods Fifty male FVB mice were divided into three subgroups to test various responses to exercise, including time- dependent response of angiogenic factors to exercise training in intact heart (n=10) and infarcted heart (n= 10), as well as exercise-induced angiogenic response in heart with myocardial infarction (MI) (n=30). The mice in the exercise-training groups were allowed to exercise daily at 1 hour per day for 7 days. Results VEGF protein expression was up-regulated by exercise training in time dependent fashion in mice with MI. Angiogenesis was evident by increased myocardial mi- crovessels observed by PECAM-1 immunohistoc-hemi- cal staining in post-MI exercise group (16.5±3.4)/0.4 mm2 versus post-MI sedentary mice (10±2.1)/0.4 mm2 (P < 0.05). Cell proliferation assessment showed significantly higher (P < 0.05 ) number of BrdU positive cells in post MI mice in exercise group as opposed to sedentary post MI mice. 2%TTC staining disclosed a profound difference in the size of MI (18.25±2.93)% in exercise group vs sedentary group (29.26±7.64)% (P< 0.05). Conclusions Activation and up-regulation of VEGF in infarcted mice heart may contributes the angiogenic response to exercise training at the early stage of myocardial infarction. This underscores the impact of exercise on angiogenesis in post myocardial infarction setting.
Objectives Little is known about the mechanism of exercise-induced angiogenic response in ischemic myocardium. This study was designed to investigate the effects of exercise training on expression of vascular endothelial growth factor and angiogenesis in infarcted heart. Methods Fifty male FVB mice were divided into three subgroups to test various responses to exercise, including time- dependent response of angiogenic factors to exercise training in intact heart (n=10) and infarcted heart (n= 10), as well as exercise-induced angiogenic response in heart with myocardial infarction (MI) (n=30). The mice in the exercise-training groups were allowed to exercise daily at 1 hour per day for 7 days. Results VEGF protein expression was up-regulated by exercise training in time dependent fashion in mice with MI. Angiogenesis was evident by increased myocardial mi- crovessels observed by PECAM-1 immunohistoc-hemi- cal staining in post-MI exercise group (16.5±3.4)/0.4 mm2 versus post-MI sedentary mice (10±2.1)/0.4 mm2 (P < 0.05). Cell proliferation assessment showed significantly higher (P < 0.05 ) number of BrdU positive cells in post MI mice in exercise group as opposed to sedentary post MI mice. 2%TTC staining disclosed a profound difference in the size of MI (18.25±2.93)% in exercise group vs sedentary group (29.26±7.64)% (P< 0.05). Conclusions Activation and up-regulation of VEGF in infarcted mice heart may contributes the angiogenic response to exercise training at the early stage of myocardial infarction. This underscores the impact of exercise on angiogenesis in post myocardial infarction setting.
