Hogan R D, Franklin T D, Avery K S, Burke K M
Am J Physiol. 1982 Jun;242(6):H996-9. doi: 10.1152/ajpheart.1982.242.6.H996.
The effect of moderate local heat stress on arteriolar tone in the cremaster muscle of anesthetized rats was investigated by direct microscopic observation. Muscle temperature was raised from the in vivo temperature of 34.5 to 38 degrees C, over a 5-min period, by elevating bath temperature. Muscle temperature, arteriolar lumen diameter, and arteriolar red blood cell velocity were continuously recorded. A number of the smallest arterioles studied (approximately 30 micrometers lumen diam) underwent a rapid and significant vasoconstriction near 36 degrees C. Denervation of the muscle eliminated the constrictor response. Addition of an alpha-blocking agent (dibenzyline to the denervated muscle unmasked the constriction, but the percent of arterioles demonstrating thermal reactivity remained decreased. We conclude that in some skeletal muscle beds a local thermoregulatory mechanism may exist whereby blood is shunted away from the tissue during heat stress at rest.
通过直接显微镜观察，研究了中度局部热应激对麻醉大鼠提睾肌小动脉张力的影响。通过提高浴温，在5分钟内将肌肉温度从体内温度34.5℃升高到38℃。连续记录肌肉温度、小动脉管腔直径和小动脉红细胞速度。许多研究的最小小动脉（管腔直径约30微米）在接近36℃时经历了快速且显著的血管收缩。肌肉去神经支配消除了收缩反应。向去神经支配的肌肉中添加α阻断剂（双苄胺）可揭示这种收缩，但表现出热反应性的小动脉百分比仍然降低。我们得出结论，在一些骨骼肌床中可能存在一种局部体温调节机制，在静息热应激期间，血液会从组织中分流出去。
