Engell D B, Maller O, Sawka M N, Francesconi R N, Drolet L, Young A J
Physiol Behav. 1987;40(2):229-36. doi: 10.1016/0031-9384(87)90212-5.
The relationship among changes in thirst sensations, blood variables, and differential fluid intake in hypohydrated humans was examined. Seven subjects were hypohydrated by 0%, 3%, 5%, and 7% of their body weight on four separate trials which were systematically randomized between subjects. Hypohydration levels were achieved with a regimen of restricted food and fluid intake and moderate heat-exercise stress. Statistically significant linear and quadratic trends were found for the intensity of several sensations with progressive hypohydration levels. In general, plasma osmolality and renin activity increased and plasma volume decreased with increasing hypohydration levels. During a one hour period of ad lib drinking, all subjects consumed insufficient fluid to rehydrate back to baseline body weights. Using regression analyses, fluid intake was predicted by the magnitude of subjective and physiological indices of hypohydration. Results demonstrate that both hypovolemia and plasma osmolality contribute significantly to fluid intake in hypohydrated humans. The results also indicate that thirst sensations make a substantial contribution to differential fluid intake in humans.
研究了水分流失的人体中口渴感觉变化、血液变量和不同液体摄入量之间的关系。七名受试者在四项独立试验中分别减重0%、3%、5%和7%（相对于其体重），试验在受试者之间系统随机安排。通过限制食物和液体摄入以及适度的热运动应激方案来实现水分流失水平。随着水分流失程度的逐渐增加，几种感觉的强度呈现出统计学上显著的线性和二次趋势。一般来说，随着水分流失程度的增加，血浆渗透压和肾素活性升高，血浆量减少。在自由饮水的一小时期间，所有受试者摄入的液体不足以补充水分至基线体重。通过回归分析，根据水分流失的主观和生理指标的大小预测液体摄入量。结果表明，血容量不足和血浆渗透压都对水分流失的人体的液体摄入有显著影响。结果还表明，口渴感觉对人类不同的液体摄入量有很大贡献。
