Effects of blood pressure on force production in cat and human muscle.
Effects of blood pressure on force production in cat and human muscle.
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血压对猫和人类肌肉产生力量的影响。
DOI：
10.1152/jappl.1987.63.2.834
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发表时间：
1987
影响因子：
3.3
通讯作者：
D. McCloskey
中科院分区：
文献类型：
--
作者：
S. F. Hobbs;D. McCloskey
在麻醉猫中，将局部动脉压从125降低到75Torr，比目鱼肌和腓肠肌内侧的血流量(53+/-5%)和力量产生(57+/-7%)减少。在这些肌肉中，力量是由有氧的、缓慢疲劳的纤维产生的。动脉压的类似降低并不影响主要含有快速疲劳纤维的尾侧肌的力量产生。在人类受试者中，在有节奏的恒力收缩中，踝关节伸展肌产生的肌电随着收缩肌肉在腿部向上倾斜时上升到心脏上方而增加。这表明，在给定的激活水平下，活跃肌肉纤维的力量产生随着肌肉灌流压力的下降而下降，因此需要增加肌肉活动来维持标准的收缩。因为有氧纤维导致了这些收缩，所以人类肌肉纤维的力量产生似乎对灌流压力的微小变化很敏感，可能还有血液流动。已形成的肌力对血压的关键依赖性对运动控制很重要，在运动过程中也可能在心血管控制中发挥重要作用。
In anesthetized cats reducing local arterial pressure from 125 to 75 Torr decreased blood flow (53 +/- 5%) and force production (57 +/- 7%) in soleus and medial gastrocnemius. Force was produced in these muscles by aerobic, slowly fatiguing fibers. Similar reductions in arterial pressure did not affect force production in caudofemoralis, which contains mainly fast-fatiguing fibers. In human subjects the electromyogram produced by the ankle extensors during rhythmic constant-force contractions increased as the contracting muscles were raised above the heart during legs-up tilt. This suggests that force production of active muscle fibers at a given level of activation fell with muscle perfusion pressure, thus requiring augmentation of muscle activity to sustain the standard contractions. Because aerobic fibers contributed to these contractions, it appears that force production of human muscle fibers is sensitive to small changes in perfusion pressure and, presumably, blood flow. The critical dependence of developed muscular force on blood pressure is of importance to motor control and may also play a significant role in cardiovascular control during exercise.