Studies on the interaction of regulatory mechanisms of body temperature, circulation and body fluid.

热应激导致皮肤血管扩张和热脱水。以补液过程和中心静脉压控制为重点，研究了这种情况下的调节反应。在人类受试者中，通过饮用来补充的汗水损失通常低于汗水损失，这种现象被称为自愿脱水。在本实验中，我们明确指出这种脱水是由于体液的渗透稀释造成的，为了充分恢复损失，需要补充流失的盐。此外，我们发现单独提供时，能够替代大鼠热脱水的NaCl浓度在0.2 ~ 0.9%之间。在大鼠选择NaCl溶液时，先服用约50 meq/l的NaCl溶液约2小时，然后再消耗约120 meq/l的NaCl溶液。研究犬和大鼠控制性静脉压（CVP）的调节机制：全脊髓阻滞和肾上腺素能激动剂均显示交感神经系统参与了犬控制性静脉压的调节。在狗身上也发现了CVP参与终止饮酒行为的过程。使用热适应大鼠，观察到热暴露时血管顺应性降低。用不同水合水平的大鼠，观察CVP对外周血管总阻力的反馈控制。在这些实验的基础上，连续监测大鼠运动时循环血容量的变化以及血钠、钾浓度的变化。基于这些结果，描述热应激下循环反应与血容量或体液调节之间的相互作用成为可能。

Heat stress causes cutaneous vasodilation and thermal dehydration. Regulatory responses under this condition were studied focusing rehydration process and control of central venous pressure.In human subjects, the replacement of sweat loss by drinking is usually lower than sweat loss, and the phenomenon is known as voluntary dehydration in this experiment we made it clear that this dehydration is due to osmotic dilution of body fluid and for the full restitution of the loss, replacement of lost salt is required. In addition, we showed that NaCl concentration which enable to replace thermal dehydration in rats was from 0.2 to 0.9% when provided alone. When rats were allowed to choose NaCl solution, about 50 meq/l of NaCl solution was taken for about 2 hours and then that of about 120 meq/l was consumed.The regulatory mechanism of contral venous pressure (CVP) was analyzed using dogs and rats: The involvement of sympathetic nervous system in the regulation of CVP was shown in dogs by total spinal block and adrenergic agonist. The involvement of CVP in the termination of drinking behavior was also shown in dog. Using heat acclimatized rats, lowering of vascular compliance during heat exposure was observed. Using rats with different hydration levels, feedback control of total peripheral vascular resistance from CVP was shown. In addition to these experiments, the changes in circulating blood volume was monitored continuously together with the change in blood sodium and potassium concentration during exercise in rats.Based on these results, it became possible to depict the interaction between circulatory responses and blood volume or body fluid regulation under heat stress.