Exercise training alters myogenic responses in porcine coronary resistance arteries.
Exercise training alters myogenic responses in porcine coronary resistance arteries.
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DOI：
10.1152/jappl.1993.75.6.2677
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发表时间：
1993-12
影响因子：
3.3
通讯作者：
J. Muller;P. Myers;M. Laughlin
中科院分区：
文献类型：
--
作者：
J. Muller;P. Myers;M. Laughlin
本研究的目的是检验运动训练减弱猪冠状动脉阻力动脉的肌源性反应性的假设。将 24 只雌性尤卡坦小型猪随机分为两组，每组 12 头：运动训练组 (ET) 和静坐控制组 (SED)。 ET 猪在电机驱动的跑步机上训练 16-22 周，而 SED 猪仍被限制在猪栏内。训练后，与 SED 猪相比，ET 猪的心脏重量与体重比、骨骼肌氧化能力和运动耐量均显着增加。分离直径75-150微米的冠状动脉阻力动脉，用于体外评估在没有腔内血流的情况下对腔内压力变化的肌原性反应。 ET 和 SED 猪的冠状动脉阻力动脉在 40 mmHg 腔内压力下产生自发张力。 ET 和 SED 猪的冠状动脉阻力动脉中，管腔内压力 < 40 mmHg 时测得的主动直径变化相似。当压力升至 40 mmHg 以上时，ET 猪的冠状动脉阻力动脉的肌源性收缩更大，直径显着减少表明。在 60 和 70 mmHg 管腔内压力下，ET 猪的阻力动脉收缩分别增加 8% 和 16%。用硝普钠（100 µM）最大程度松弛后，ET 和 SED 猪的冠状动脉阻力动脉中响应管腔内压力从 10 至 80 mmHg 变化而测量的被动直径变化没有显着差异。我们的结论是，与我们的假设相反，猪的运动训练增强了冠状动脉阻力动脉的肌源性收缩反应。（摘要截断为 250 字）
The purpose of this study was to test the hypothesis that myogenic responsiveness in porcine coronary resistance arteries is attenuated by exercise training. Twenty-four female Yucatan miniature swine were randomly separated into two groups of 12 pigs: exercise trained (ET) and sedentary control (SED). The ET pigs were trained on a motor-driven treadmill for 16-22 wk while the SED pigs remained confined to their pens. After training, heart weight-to-body weight ratio, skeletal muscle oxidative capacity, and exercise tolerance were significantly increased in ET pigs compared with SED pigs. Coronary resistance arteries 75-150 microns diam were isolated for in vitro evaluation of myogenic responses to changes in intraluminal pressure in the absence of intraluminal flow. Coronary resistance arteries from ET and SED pigs developed spontaneous tone at 40 mmHg intraluminal pressure. Active changes in diameter measured in response to intraluminal pressures < 40 mmHg were similar in coronary resistance arteries from ET and SED pigs. When pressure was raised above 40 mmHg, myogenic constriction was greater in coronary resistance arteries from ET pigs, as indicated by significantly greater reductions in diameter. At 60 and 70 mmHg intraluminal pressure, constriction was 8 and 16% greater, respectively, in resistance arteries from ET pigs. After maximal relaxation with sodium nitroprusside (100 microM), passive diameter changes measured in response to changes in intraluminal pressure from 10 to 80 mmHg were not significantly different in coronary resistance arteries from ET and SED pigs. We conclude that, contrary to our hypothesis, exercise training in pigs enhances myogenic constrictor responses in coronary resistance arteries.(ABSTRACT TRUNCATED AT 250 WORDS)