Williamson J W, Olesen H L, Pott F, Mitchell J H, Secher N H
Copenhagen Muscle Research Centre, Department of Anaesthesia, Rigshospitalet, University of Copenhagen, Denmark.
Acta Physiol Scand. 1996 Apr;156(4):429-34. doi: 10.1046/j.1365-201X.1996.472186000.x.
Neural control of the circulation during static two-leg exercise was evaluated in 10 subjects. External compression of the legs was employed to assess muscle mechano-receptor influence by achieving the same intramuscular pressure (80 mmHg) as developed during exercise. The muscle metabo-reflex contribution was assessed by post-exercise muscle ischaemia, and the influence from higher centres in the central nervous system ('central command') was taken as the part of the response that could not be accounted for by the two reflex contributions. During static exercise, mean arterial pressure was higher (26 +/- 3 mmHg; P < 0.01) as compared with leg compression (10 +/- 2 mmHg) and with post-exercise muscle ischaemia (11 +/- 2 mmHg). Heart rate (25 +/- 4 b.p.m.) and cardiac output (0.8 +/- 0.3 L min-1) were increased only during static exercise (P < 0.05). Increase in total peripheral resistance were similar during static exercise, post-exercise muscle ischaemia and leg compression. The pressor response to static exercise with a large muscle group was equally attributable to mechanical and metabolic stimulation of afferent nerves; and the two influences were redundant in their effect on total peripheral resistance. In contrast, the influence from central command was directed to the heart with elevation of its rate and minute volume.
对10名受试者在静态双腿运动期间的循环神经控制进行了评估。通过施加腿部外部压力来评估肌肉机械感受器的影响，使肌肉内压力达到运动时产生的相同水平（80 mmHg）。通过运动后肌肉缺血来评估肌肉代谢反射的作用，而将中枢神经系统中高级中枢的影响（“中枢指令”）视为无法由这两种反射作用解释的那部分反应。在静态运动期间，平均动脉压（26±3 mmHg；P<0.01）高于腿部加压时（10±2 mmHg）和运动后肌肉缺血时（11±2 mmHg）。心率（25±4次/分钟）和心输出量（0.8±0.3升/分钟）仅在静态运动期间增加（P<0.05）。在静态运动、运动后肌肉缺血和腿部加压期间，总外周阻力的增加相似。对大肌群静态运动的升压反应同样归因于传入神经的机械和代谢刺激；并且这两种影响对总外周阻力的作用是多余的。相比之下，中枢指令的影响是通过提高心率和每分输出量作用于心脏。
