Exercise training improves left ventricular contractile response to beta-adrenergic agonist.
Exercise training improves left ventricular contractile response to beta-adrenergic agonist.
复制标题
运动训练可改善左心室收缩对β-肾上腺素能激动剂的反应。
DOI：
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发表时间：
1992
影响因子：
3.3
通讯作者：
A. Ehsani
中科院分区：
文献类型：
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作者：
R. Spina;T. Ogawa;A. Coggan;J. Holloszy;A. Ehsani
为了确定耐力运动训练是否可以改善左心室功能对β-肾上腺素能刺激的反应，年轻健康的久坐不动的受试者（10名女性和6名男性）进行了研究之前和之后的12周的耐力运动训练。训练包括3天/周的间歇训练（跑步和骑自行车）和3天/周的连续跑步40分钟。训练导致最大摄氧量从41.0 +/- 2增加到49.3 +/- 2 ml.kg-1. min-1（P <0.01）。在基础条件下和异丙肾上腺素诱导的β-肾上腺素能刺激期间，通过二维超声心动图评价左心室功能。基础条件下的缩短分数（FS）在训练后没有变化（36 +/- 1 vs. 36 +/- 2%）。在最高剂量异丙肾上腺素期间，训练前FS为52 +/- 1%，训练后为56 +/- 1%（P <0.05）。在收缩末期室壁应力（σ es）的变化相当时，训练后异丙肾上腺素诱导的FS增加显著更大（13 +/- 1 vs. 17 +/-2%，P <0.01）。此外，在异丙肾上腺素输注过程中，在训练状态下，收缩末期尺寸在相似的σ es变化下有更大的减小（训练前为-4.6 +/- 0.1 mm vs.训练后为-7.0 +/- 0.1 mm，P <0.01）。在异丙肾上腺素输注期间，训练和未训练状态之间的舒张末期尺寸没有同时变化，表明在可比较的σ es水平下，前负荷没有显著变化。（250字处删节）
To determine whether endurance exercise training can improve left ventricular function in response to beta-adrenergic stimulation, young healthy sedentary subjects (10 women and 6 men) were studied before and after 12 wk of endurance exercise training. Training consisted of 3 days/wk of interval training (running and cycling) and 3 days/wk of continuous running for 40 min. The training resulted in an increase in maximal O2 uptake from 41.0 +/- 2 to 49.3 +/- 2 ml.kg-1.min-1 (P less than 0.01). Left ventricular function was evaluated by two-dimensional echocardiography under basal conditions and during beta-adrenergic stimulation induced by isoproterenol infusion. Fractional shortening (FS) under basal conditions was unchanged after training (36 +/- 1 vs. 36 +/- 2%). During the highest dose of isoproterenol, FS was 52 +/- 1% before and 56 +/- 1% after training (P less than 0.05). At comparable changes in end-systolic wall stress (sigma es), the increase in FS induced by isoproterenol was significantly larger after training (13 +/- 1 vs. 17 +/- 2%, P less than 0.01). Furthermore there was a greater decrease in end-systolic dimension at similar changes in sigma es in the trained state during isoproterenol infusion (-4.6 +/- 0.1 mm before vs. -7.0 +/- 0.1 mm after training, P less than 0.01). There were no concurrent changes in end-diastolic dimension between the trained and untrained states during isoproterenol infusion, suggesting no significant changes in preload at comparable levels of sigma es.(ABSTRACT TRUNCATED AT 250 WORDS)