Aortic baroreflex control of heart rate during hypertensive stimuli: effect of fitness.
Aortic baroreflex control of heart rate during hypertensive stimuli: effect of fitness.
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高血压刺激期间主动脉压力反射对心率的控制：健身的效果。
DOI：
10.1152/jappl.1993.74.4.1555
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发表时间：
1993
期刊：
影响因子：
--
通讯作者：
Raven,PB
中科院分区：
文献类型：
--
作者：
Shi,X;Andresen,JM;Potts,JT;Foresman,BH;Stern,SA;Raven,PB
我们研究了主动脉压力反射控制的心率（HR）在7个健康的年轻男子的平均健身（AF）和7个高健身（HF）。通过最大摄氧量（AF = 42.9 +/- 1.1，HF = 62.3 +/- 1.8 ml.kg-1.min-1）确定健康水平。在平均动脉压稳态增加时测定主动脉压力反射对心率的控制（MAP; AF，+15.0 +/- 2.1和HF，+18.3 +/- 0.8 mmHg），苯肾上腺素（PE）输注联合颈部正压（NP; AF，18 +/- 2.0和HF，20 +/- 0.8 mmHg）以抵消增加的颈动脉窦压力，并使用低水平的下体负压以抵消增加的中心静脉压。在PE输注期间，MAP或NP升高无组间差异，两组内MAP也无阶段差异。然而，孤立的心脏-主动脉压力感受性反射增益（即，在PE + NP和PE + NP +下体负压下，HF受试者的Δ HR/Δ MAP（0.16 +/- 0.02和0.14 +/- 0.03次/分-1.mmHg-1）显著低于AF受试者（0.52 +/- 0.08和0.59 +/- 0.07次/分-1.mmHg-1）。我们的结论是，在MAP的稳态增加，主动脉压力感受器反射控制的敏感性HR显着低于HF比AF的主题。
We examined the aortic baroreflex control of heart rate (HR) in seven healthy young men of average fitness (AF) and seven of high fitness (HF). The fitness level was determined by maximal oxygen uptake (AF = 42.9 +/- 1.1, HF = 62.3 +/- 1.8 ml.kg-1.min-1). Aortic baroreflex control of HR was determined during a steady-state increase of mean arterial pressure (MAP; AF, +15.0 +/- 2.1 and HF, +18.3 +/- 0.8 mmHg) with phenylephrine (PE) infusion combined with positive neck pressure (NP; AF, 18 +/- 2.0 and HF, 20 +/- 0.8 mmHg) to counteract the increased carotid sinus pressure and with low levels of lower body negative pressure to counteract the increased central venous pressure. There was no group difference in the increased MAP or NP, nor was there stage difference in MAP within either group during PE infusion. However, the isolated cardiac-aortic baroreflex gains (i.e., delta HR/delta MAP) were significantly less in the HF (0.16 +/- 0.02 and 0.14 +/- 0.03 beats.min-1.mmHg-1) than in the AF (0.52 +/- 0.08 and 0.59 +/- 0.07 beats.min-1.mmHg-1) subjects at PE + NP and PE + NP + lower body negative pressure. We concluded that during steady-state increases in MAP, the sensitivity of aortic baroreflex control of HR was significantly less in the HF than in the AF subjects.