Mejsnar J, Kolár F, Malá J
Physiol Bohemoslov. 1980;29(2):151-60.
The authors studied the effect of the blood perfusion rate and of noradrenaline (NA) on the oxygen consumption of the isolated hind limb and on the partly - and vascularly completely - isolated cranial gracilis muscle of cold-acclimated rats. Oxygen consumption of the limb was stimulated by a raised perfusion rate together with growth of the oxygen extraction coefficient and by NA, which also raised oxygen consumption when the perfusion rate was constant. Oxygen consumption of the partly isolated muscle was likewise stimulated by a raised perfusion rate, but without a simultaneous increase in the oxygen extraction coefficient. In the vascularly completely isolated muscle, a raised perfusion rate had only a transient stimulant effect on oxygen consumption. In the partly and the completely isolated muscle, NA raised the arteriovenous difference in the blood oxygen content and organ resistance independently of each other. The calorigenic effect of NA, which was determined by the ratio of the two effects, did not exceed 34% above the resting level. The conclusions that the thermogenesis of resting muscle can be controlled by the blood flow on the basis of a mechanism other than the limitation of oxygen or substrates supply, and that NA acts independently of oxygen extraction from the blood and of the blood flow, show the blood flow to be a mechanism at organ level, which participates in the control of nonshivering thermogenesis in skeletal muscle.
作者研究了血液灌注速率和去甲肾上腺素（NA）对冷适应大鼠离体后肢以及部分血管隔离和完全血管隔离的颅侧股薄肌耗氧量的影响。灌注速率升高以及氧摄取系数增加会刺激后肢的耗氧量，NA也会刺激后肢耗氧量，且在灌注速率恒定时NA同样会增加耗氧量。部分隔离肌肉的耗氧量同样会因灌注速率升高而受到刺激，但氧摄取系数不会同时增加。在完全血管隔离的肌肉中，灌注速率升高对耗氧量仅有短暂的刺激作用。在部分隔离和完全隔离的肌肉中，NA分别独立地增加了血液氧含量的动静脉差值和器官阻力。由这两种作用的比值所确定的NA的产热效应，相较于静息水平，增幅不超过34%。基于氧气或底物供应受限以外的机制，静息肌肉的产热可由血流控制，且NA的作用独立于从血液中摄取氧气和血流，这些结论表明血流是一种器官水平的机制，参与骨骼肌非寒战产热的控制。
