Horowitz M, Samueloff S, Adler J H
J Appl Physiol Respir Environ Exerc Physiol. 1978 Apr;44(4):585-8. doi: 10.1152/jappl.1978.44.4.585.
Body water distribution after "acute dehydration" treatment (37 degrees C) was studied in Psammonys obesus before and after acclimation at 34 +/- 1 degrees C for 16-18 days. Determinations of water compartment volumes were performed on anaesthetized (thiopental sodium) nephrectomized animals. Plasma volume (PV) and extracellular volume (ECV) were measured by T-1824 and [14C]inulin, respectively. Total body water was determined after desiccating the animals. Albumin outflux was calculated from the half-life (T1/2) of T-1824 and total plasma albumin mass. Nonacclimated animals conserved PV as long as dehydration did not exceed 10-11% loss of body wt. This conservation was at the expense of ECV and was associated with diminished albumin outflux (T1/2 T-1824 approached infinity). With increased dehydration PV retention failed and a resumption of albumin outflux occurred. Acclimation resulted in diminished albumin outflux in both control and dehydrated animals (T1/2 T-1824 approached infinity). Most of the water lost during dehydration was of intracellular origin. It was concluded that reduction in permeability of the capillary bed during dehydration and acclimatization plays an important role in PV and ECV regulation.
在肥胖沙鼠于34±1℃适应16 - 18天前后，研究了“急性脱水”处理（37℃）后的机体水分分布情况。对麻醉（硫喷妥钠）去肾动物进行了水腔室容积的测定。分别用T - 1824和[14C]菊粉测量血浆容积（PV）和细胞外容积（ECV）。在使动物干燥后测定总体水含量。根据T - 1824的半衰期（T1/2）和血浆白蛋白总量计算白蛋白外流。只要脱水不超过体重的10 - 11%，未适应的动物就能保留PV。这种保留是以牺牲ECV为代价的，并且与白蛋白外流减少有关（T - 1824的T1/2接近无穷大）。随着脱水程度增加，PV保留失败，白蛋白外流恢复。适应导致对照动物和脱水动物的白蛋白外流均减少（T - 1824的T1/2接近无穷大）。脱水过程中丢失的大部分水分来自细胞内。得出的结论是，脱水和适应过程中毛细血管床通透性的降低在PV和ECV调节中起重要作用。
