Barney C C, Vergoth C, Renkema L A, Meeuwsen K W
Department of Biology, Hope College, Holland, MI 49423, USA.
Physiol Behav. 1995 Aug;58(2):329-35. doi: 10.1016/0031-9384(95)00059-r.
Temporal variation in spontaneous water intake in rats is well established but little is known about temporal variation in water intake following dehydration. In the present study different male Sprague-Dawley strain rats were exposed without water for 3 h to either a 25 degrees C or a 40 degrees C environment every 4 h for 20 h. The rats were then allowed access to water in a 25 degrees C environment for 2 h. Rats exposed to 25 degrees C showed significant temporal variation in evaporative water loss, urine output, urine sodium and potassium excretion, water intake, and percent rehydration with higher values occurring during the night. Rats exposed to 40 degrees C had greater evaporative water loss, urine sodium excretion, feces output and water intake than the rats exposed to 25 degrees C and had temporal variations which were similar to those of the rats exposed to 25 degrees C. The robust effects of thermal-dehydration on water balance in rats are additive to rather than interactive with the effects of time of day.
大鼠自发饮水量的时间变化已得到充分证实，但关于脱水后饮水量的时间变化却知之甚少。在本研究中，将不同的雄性斯普拉格-道利品系大鼠每4小时在无水条件下暴露于25℃或40℃环境中3小时，持续20小时。然后让大鼠在25℃环境中饮水2小时。暴露于25℃的大鼠在夜间蒸发失水量、尿量、尿钠和钾排泄量、饮水量以及补水百分比方面表现出显著的时间变化，且数值较高。暴露于40℃的大鼠比暴露于25℃的大鼠有更大的蒸发失水量、尿钠排泄量、粪便排出量和饮水量，并且其时间变化与暴露于25℃的大鼠相似。热脱水对大鼠水平衡的强烈影响是与一天中的时间效应相加而非相互作用。
