Exercise training changes autonomic cardiovascular balance in mice
Exercise training changes autonomic cardiovascular balance in mice
复制标题
DOI：
10.1152/japplphysiol.00870.2003
复制
发表时间：
2004-06-01
影响因子：
3.3
通讯作者：
Irigoyen, MC
中科院分区：
文献类型：
--
作者：
De Angelis, K;Wichi, RB;Irigoyen, MC
为探讨运动训练对小鼠心血管功能的影响，进行了实验研究。测定了清醒、无拘束的雄性C57/6J久坐小鼠(n=8)和训练小鼠(n=8)的心率、动脉压、压力反射敏感性和自主心率控制。运动训练方案使用跑步机(1h/d；5d/wk，4wk)。用硝普钠诱发的心动过速和苯肾上腺素引起的心动过缓反应评价压力感受性反射的敏感性。用甲基阿托品和心得安测定自主控制心率和内源性心率。与久坐不动的小鼠相比，训练组小鼠出现静息心动过缓[485+/-9次/分钟比612+/-5次/分(次/分)]，而平均动脉压在两组间没有差别(106+/-2次比108+/-3毫米汞柱)。压力感受性反射介导的心动过速在训练组显著增加(6.97+/-0.97比1.6+/-0.21次/分/毫米汞柱，训练组与久坐组相比)，而压力感受性反射介导的心动过缓在训练中没有改变。甲基阿托品诱发的心动过速在训练组显著增加(训练组139+/-12次/分对静坐时40+/-9次/分)，而心得安效应在训练组显著降低(49+/-11次/分比97+/-11次/分)。不同组间的内在心率相似。总而言之，动态运动训练导致了小鼠静止性心动过缓，并改善了压力感受性反射介导的心动过速。这些变化可能与迷走神经增加和交感神经张力降低有关，类似于在人类中观察到的运动反应。
Experiments were performed to investigate the influence of exercise training on cardiovascular function in mice. Heart rate, arterial pressure, baroreflex sensitivity, and autonomic control of heart rate were measured in conscious, unrestrained male C57/6J sedentary (n = 8) and trained mice (n = 8). The exercise training protocol used a treadmill (1 h/day; 5 days/wk for 4 wk). Baroreflex sensitivity was evaluated by the tachycardic and bradycardic responses induced by sodium nitroprusside and phenylephrine, respectively. Autonomic control of heart rate and intrinsic heart rate were determined by use of methylatropine and propranolol. Resting bradycardia was observed in trained mice compared with sedentary animals [ 485 +/- 9 vs. 612 +/- 5 beats/min (bpm)], whereas mean arterial pressure was not different between the groups (106 +/- 2 vs. 108 +/- 3 mmHg). Baroreflex-mediated tachycardia was significantly enhanced in the trained group (6.97 +/- 0.97 vs. 1.6 +/- 0.21 bpm/mmHg, trained vs. sedentary), whereas baroreflex- mediated bradycardia was not altered by training. The tachycardia induced by methylatropine was significantly increased in trained animals (139 +/- 12 vs. 40 +/- 9 bpm, trained vs. sedentary), whereas the propranolol effect was significantly reduced in the trained group (49 +/- 11 vs. 97 +/- 11 bpm, trained vs. sedentary). Intrinsic heart rate was similar between groups. In conclusion, dynamic exercise training in mice induced a resting bradycardia and an improvement in baroreflex- mediated tachycardia. These changes are likely related to an increased vagal and decreased sympathetic tone, similar to the exercise response observed in humans.