Okuno T, Yawata T, Nose H, Morimoto T
Department of Physiology, Kyoto Prefectural University of Medicine, Japan.
J Appl Physiol (1985). 1988 Jun;64(6):2438-43. doi: 10.1152/jappl.1988.64.6.2438.
Albino rats were thermally dehydrated (approximately 8% of body wt), divided into five groups, and given tap water or 0.2, 0.45, 0.9, or 2.0% NaCl solution ad libitum for 16 h. Rats given 0.9 or 0.45% NaCl solution regained fluid loss completely in 3-3.5 h, whereas those given 0.2% solution became fully rehydrated at 10 h. The rats in the tap water and 2.0% NaCl groups were only 78 and 59% rehydrated, respectively, within 16 h. Na balance was positive in the 0.9% NaCl group by about five times the amount of the cations lost during the dehydration period. A positive balance of Na was also observed in the 0.45 (approximately 250%) and 2.0% NaCl groups (300%), whereas the 0.2% NaCl group regained lost water and Na simultaneously at 10 h. With tap water, additional loss of cations was observed. These findings show that for the replacement of water due to thermal dehydration there is a range of NaCl concentration with which the rats can rehydrate with the mutual cooperation of thirst, salt appetite, and kidney function.
将白化大鼠进行热脱水（约占体重的8%），分为五组，随意给予自来水或0.2%、0.45%、0.9%或2.0%的氯化钠溶液，持续16小时。给予0.9%或0.45%氯化钠溶液的大鼠在3 - 3.5小时内完全恢复了失水量，而给予0.2%溶液的大鼠在10小时时完全补水。自来水组和2.0%氯化钠组的大鼠在16小时内分别仅恢复了78%和59%的失水量。0.9%氯化钠组的钠平衡为正，约为脱水期丢失阳离子量的五倍。在0.45%（约250%）和2.0%氯化钠组（300%）也观察到钠的正平衡，而0.2%氯化钠组在10小时时同时恢复了丢失的水分和钠。饮用自来水时，观察到阳离子的额外丢失。这些发现表明，对于热脱水引起的水分补充，存在一定范围的氯化钠浓度，大鼠可通过口渴、摄盐欲和肾功能的相互配合来实现补水。
