Neural control of the circulation during exercise: insights from the 1970–1971 Oxford studies
Neural control of the circulation during exercise: insights from the 1970–1971 Oxford studies
复制标题
运动过程中循环的神经控制：来自 1970-1971 年牛津研究的见解
DOI：
10.1113/expphysiol.2011.058156
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发表时间：
2012
影响因子：
2.7
通讯作者：
Jere H. Mitchell
中科院分区：
文献类型：
--
作者：
Jere H. Mitchell
在运动期间，心血管反应的幅度与运动强度密切匹配。在实现这种适当的匹配中，自主神经系统发挥了重要作用。有两种机制被假定来调节这种反应。在一种机制中，心脏和血管的自主神经活动的变化是由大脑中央区域产生的信号引起的，而在另一种机制中，变化是由收缩的骨骼肌产生的信号引起的。在1970年至1971年，在牛津大学进行了两项研究，进一步加深了我们对这两种机制的理解。其中一项研究表明，猫的骨骼肌收缩时产生的反射会反射性地增加血压和心率，而有髓鞘的（III或A组）和无髓鞘的（IV或C组）传入神经纤维对此起了作用。在第二项研究中，在人类中显示，在固定力的静态收缩期间，中枢机制也可以增加血压和心率。骨骼肌的腱振动引起不自主的反射性收缩。利用这种效应，中央指挥部需要产生相同的紧张发展被减少或增加。当用较少的中央指令实现相同的力时，心血管反应减少，而用更多的中央指令增加。这表明，来自大脑高级中枢的下行运动指令对心血管对运动的反应有影响。
During exercise the magnitude of the cardiovascular response is closely matched to the intensity of the exercise. In achieving this appropriate matching, an important role is played by the autonomic nervous system. Two mechanisms have been postulated to regulate this response. In one mechanism the changes in autonomic nerve activity to the heart and blood vessels are caused by signals arising in a central area of the brain and in the other mechanism the changes are caused by signals arising in the contracting skeletal muscle. In 1970–71 two studies were performed in Oxford which furthered our understanding of these two mechanisms. In one of these studies it was shown in cats that a reflex arising in the contracting skeletal muscle reflexly increased blood pressure and heart rate and that the thinly myelinated (Group III or A Ō) and the unmyelinated (Group IV or C) afferent nerve fibers were responsible. In the second of these studies it was shown in humans that a central mechanism could also increase the blood pressure and heart rate during static contraction at a fixed force. Tendon vibration of a skeletal muscle induces an involuntary reflex contraction. Utilizing this effect the central command needed to produce the same tension development was reduced or increased. When the same force was achieved with less central command the cardiovascular response was reduced and with more central command was increased. This demonstrated that descending motor commands from higher brain centers have an effect on the cardiovascular response to exercise.