Joyner Michael J, Casey Darren P
Department of Anesthesiology, Mayo Clinic, Rochester, Minnesota; and Department of Physical Therapy and Rehabilitation Science, University of Iowa, Iowa City, Iowa.
Physiol Rev. 2015 Apr;95(2):549-601. doi: 10.1152/physrev.00035.2013.
This review focuses on how blood flow to contracting skeletal muscles is regulated during exercise in humans. The idea is that blood flow to the contracting muscles links oxygen in the atmosphere with the contracting muscles where it is consumed. In this context, we take a top down approach and review the basics of oxygen consumption at rest and during exercise in humans, how these values change with training, and the systemic hemodynamic adaptations that support them. We highlight the very high muscle blood flow responses to exercise discovered in the 1980s. We also discuss the vasodilating factors in the contracting muscles responsible for these very high flows. Finally, the competition between demand for blood flow by contracting muscles and maximum systemic cardiac output is discussed as a potential challenge to blood pressure regulation during heavy large muscle mass or whole body exercise in humans. At this time, no one dominant dilator mechanism accounts for exercise hyperemia. Additionally, complex interactions between the sympathetic nervous system and the microcirculation facilitate high levels of systemic oxygen extraction and permit just enough sympathetic control of blood flow to contracting muscles to regulate blood pressure during large muscle mass exercise in humans.
本综述聚焦于人类运动过程中流向收缩骨骼肌的血流是如何被调节的。其观点是，流向收缩肌肉的血流将大气中的氧气与消耗氧气的收缩肌肉联系起来。在此背景下，我们采用自上而下的方法，回顾人类静息和运动时氧气消耗的基础知识、这些数值如何随训练而变化，以及支持它们的全身血流动力学适应情况。我们着重介绍了20世纪80年代发现的运动时极高的肌肉血流反应。我们还讨论了收缩肌肉中导致这些高血流量的血管舒张因子。最后，讨论了收缩肌肉对血流的需求与最大全身心输出量之间的竞争，这是人类在进行大量肌肉群运动或全身运动时对血压调节的一个潜在挑战。目前，没有一种占主导地位的舒张机制能够解释运动性充血。此外，交感神经系统与微循环之间的复杂相互作用促进了高水平的全身氧气摄取，并在人类进行大量肌肉群运动时，允许对流向收缩肌肉的血流进行足够的交感神经控制以调节血压。
