Resistance and Venous Oxygen Dynamics during Sinusoidal Exercise of Dog Skeletal Muscle
Resistance and Venous Oxygen Dynamics during Sinusoidal Exercise of Dog Skeletal Muscle
复制标题
狗骨骼肌正弦运动期间的阻力和静脉氧动力学
DOI：
10.1161/01.res.33.3.337
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发表时间：
1973
影响因子：
20.1
通讯作者：
H. Sparks
中科院分区：
文献类型：
--
作者：
D. Mohrman;H. Sparks
我们观察了血管阻力和静脉血氧饱和度对正弦调制持续运动的反应。刺激频率在0.005.5~1 Hz之间正弦变化，调制频率在0.0 5~0.0 5 Hz之间变化。静脉氧气反应被校正，以消除由于血管和导管传输引起的离散度。随着调制频率的增加，阻力和静脉血O2对刺激频率变化的反应幅度均减小。阻力响应的动态特性依赖于流速。在高恒定流量(56±8ml/100gmin−1)下，阻力反应遵循更高的调制频率(波德角频率=0.016±0.003 Hz)，而在低恒定流量(25±7ml/100gmin−1)下(波德角频率=0.0049±0.0006 Hz)。血流对静脉饱和反应的动态影响不明显。在低恒流范围内，血管阻力和静脉血氧饱和度对运动频率正弦调制的反应具有相似的动力学特征。这一发现表明，氧化代谢可能与低流量时阻力的变化有关。然而，在高恒定流量下，四只狗中有三只的血管阻力反应遵循更高的调制频率，而没有幅度损失。在某些假设下，氧化代谢的变化是否与高恒定流量下血管阻力的变化有关是值得怀疑的。在本实验的条件下，血管阻力似乎至少由两种机制控制，其中较慢的一种可能与氧化代谢有关。
We observed the response of vascular resistance and venous oxygen (O2) saturation to sinusoidally modulated continuous exercise of the isolated dog calf. Stimulus frequency was varied sinusoidally between 0.5 Hz and 1 Hz with modulation frequencies ranging from 0.005 Hz to 0.05 Hz. Venous O2 responses were corrected for dispersion due to vascular and catheter transit. As modulation frequency was increased, the amplitude of the response of both resistance and venous O2 to changing stimulation frequency decreased. The dynamics of the resistance response depended on flow rate. At high constant flow (56 ±8 ml/100 g min−1) the resistance response followed higher modulation frequencies without loss of amplitude (Bode corner frequency = 0.016 ± 0.003 Hz) than it did at low constant flow (25 ± 7 ml/100 g min−1) (Bode corner frequency = 0.0049 ± 0.0006 Hz). The dynamics of the venous Osaturation response were not significantly altered by flow. In the low constant-flow range, vascular resistance and venous O2 saturation had similar dynamics in response to sinusoidal modulation of exercise rate. This finding indicates that oxidative metabolism may be linked to the resistance changes at low flow. At high constant flow, however, the vascular resistance response followed higher modulation frequencies without loss of amplitude than did venous O2 saturation in three of four dogs. Given certain assumptions, it is doubtful that changes in oxidative metabolism are linked to changes in vascular resistance at high constant flow. Vascular resistance, under the conditions of this experiment, appeared to be controlled by at least two mechanisms, the slower of which may be related to oxidative metabolism.