University of São Paulo, School of Physical Education and Sports, Laboratory of Biochemistry, São Paulo/SP, Brazil.
Clinics (Sao Paulo). 2011;66(12):2105-11. doi: 10.1590/s1807-59322011001200017.
Aerobic exercise training prevents cardiovascular risks. Regular exercise promotes functional and structural adaptations that are associated with several cardiovascular benefits. The aim of this study is to investigate the effects of swimming training on coronary blood flow, adenosine production and cardiac capillaries in normotensive rats.
Wistar rats were randomly divided into two groups: control (C) and trained (T). An exercise protocol was performed for 10 weeks and 60 min/day with a tail overload of 5% bodyweight. Coronary blood flow was quantified with a color microsphere technique, and cardiac capillaries were quantified using light microscopy. Adenine nucleotide hydrolysis was evaluated by enzymatic activity, and protein expression was evaluated by western blot. The results are presented as the means ± SEMs (p<0.05).
Exercise training increased the coronary blood flow and the myocardial capillary-to-fiber ratio. Moreover, the circulating and cardiac extracellular adenine nucleotide hydrolysis was higher in the trained rats than in the sedentary rats due to the increased activity and protein expression of enzymes, such as E-NTPDase and 59'-nucleotidase.
Swimming training increases coronary blood flow, number of cardiac capillaries, and adenine nucleotide hydrolysis. Increased adenosine production may be an important contributor to the enhanced coronary blood flow and angiogenesis that were observed in the exercise-trained rats; collectively, these results suggest improved myocardial perfusion.
有氧运动训练可预防心血管风险。规律运动可促进与多种心血管益处相关的功能和结构适应性。本研究旨在探讨游泳训练对正常血压大鼠冠状动脉血流、腺苷产生和心肌毛细血管的影响。
将 Wistar 大鼠随机分为两组：对照组（C）和训练组（T）。进行为期 10 周、每天 60 分钟的运动方案，尾部负重 5%体重。采用彩色微球技术定量冠状动脉血流，用光学显微镜定量心肌毛细血管。通过酶活性评估腺嘌呤核苷酸水解，通过 Western blot 评估蛋白表达。结果以平均值±SEM（p<0.05）表示。
运动训练增加了冠状动脉血流和心肌毛细血管与纤维的比例。此外，由于酶（如 E-NTPDase 和 59'-核苷酸酶）的活性和蛋白表达增加，循环和心脏细胞外腺嘌呤核苷酸水解在训练大鼠中高于安静大鼠。
游泳训练增加冠状动脉血流、心肌毛细血管数量和腺嘌呤核苷酸水解。腺苷产生增加可能是运动训练大鼠观察到的冠状动脉血流和血管生成增强的重要贡献因素；这些结果共同表明心肌灌注得到改善。
