Hypoxemia raises muscle sympathetic activity but not norepinephrine in resting humans.
Hypoxemia raises muscle sympathetic activity but not norepinephrine in resting humans.
复制标题
低氧血症会增加静息时的肌肉交感神经活动，但不会增加去甲肾上腺素。
DOI：
10.1152/jappl.1989.66.4.1736
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发表时间：
1989
期刊：
影响因子：
--
通讯作者：
Seals,DR
中科院分区：
文献类型：
--
作者：
Rowell,LB;Johnson,DG;Chase,PB;Comess,KA;Seals,DR
实验目的是确定中度至重度低氧血症是否会增加静息人体的骨骼肌交感神经活动（MSNA），而不会增加去甲肾上腺素（NE）和肾上腺素（E）的静脉血浆浓度。在9名健康受试者（20-34岁）中，我们测量了MSNA（腓总神经）、NE和E的静脉血浆水平、动脉血压、心率、潮气末O2和CO2，并在呼吸1）12%O2 20分钟、2）10%O2 20分钟和3）8%O2 10分钟期间（随机顺序）进行对照。在12%、10%和8% O2期间，分别有5名、6名和所有9名受试者的MSNA升高至对照组以上（P <0.01），但仅在延迟12分钟（12% O2）和4分钟（8%和10% O2）后。在呼吸12、10和8% O2的最后一分钟，MSNA（总活性）分别比对照组升高83 +/- 20、260 +/- 146和298 +/- 109%（SE）。在任何低氧血症水平下，NE均未高于对照组;仅在10%和8% O2下，E一次略微升高（P <0.05）。低氧血症期间MSNA的个体变化与心率升高或血压和潮气末CO2降低无关--两者都不总是下降。我们的结论是，在对比其他一些交感神经兴奋性刺激，如运动或冷应激，中度至重度低氧血症增加腿部MSNA不提高血浆NE在休息的人。
The experimental objective was to determine whether moderate to severe hypoxemia increases skeletal muscle sympathetic nervous activity (MSNA) in resting humans without increasing venous plasma concentrations of norepinephrine (NE) and epinephrine (E). In nine healthy subjects (20–34 yr), we measured MSNA (peroneal nerve), venous plasma levels of NE and E, arterial blood pressure, heart rate, and end-tidal O2 and CO2 before (control) and during breathing of 1) 12% O2 for 20 min, 2) 10% O2 for 20 min, and 3) 8% O2 for 10 min--in random order. MSNA increased above control in five, six, and all nine subjects during 12, 10, and 8% O2, respectively (P less than 0.01), but only after delays of 12 (12% O2) and 4 min (8 and 10% O2). MSNA (total activity) rose 83 +/- 20, 260 +/- 146, and 298 +/- 109% (SE) above control by the final minute of breathing 12, 10, and 8% O2, respectively. NE did not rise above control at any level of hypoxemia; E rose slightly (P less than 0.05) at one time only with both 10 and 8% O2. Individual changes in MSNA during hypoxemia were unrelated to elevations in heart rate or decrements in blood pressure and end-tidal CO2--neither of which always fell. We conclude that in contrast to some other sympathoexcitatory stimuli such as exercise or cold stress, moderate to severe hypoxemia increases leg MSNA without raising plasma NE in resting humans.