Cserr H F, DePasquale M, Patlak C S
Am J Physiol. 1987 Sep;253(3 Pt 2):F522-9. doi: 10.1152/ajprenal.1987.253.3.F522.
Regulation of brain water and electrolytes during acute hyperosmolal states has been studied in anesthetized rats. Rats were injected intravenously or intraperitoneally with hypertonic NaCl, mannitol, or sucrose (hyperosmolal series) or with isotonic NaCl (isosmolal controls). Terminal plasma osmolality varied from 290 to 385 mosmol/kg and the experimental duration from 15 to 120 min. Osmotically induced water loss from brain tissue for the different protocols was only 26-78% of that predicted for ideal osmotic behavior, revealing a degree of tissue volume regulation, and the brain gained Na, Cl, and K. This gain was sufficient to account quantitatively for tissue volume regulation at 120 min of hypernatremia but not at shorter times or during mannitol- or sucrose-induced hyperosmolality. Water loss and electrolyte uptake occur simultaneously, over 30 min, which limits the degree of brain shrinkage. Results of this analysis of the time course and magnitude of tissue electrolyte gain during acute hyperosmolality form the basis for the following two studies of the volume regulatory influx of electrolyte from plasma and CSF, respectively.
在麻醉大鼠中研究了急性高渗状态下脑水和电解质的调节。大鼠静脉内或腹腔内注射高渗氯化钠、甘露醇或蔗糖（高渗系列）或等渗氯化钠（等渗对照）。终末血浆渗透压在290至385毫摩尔/千克之间变化，实验持续时间为15至120分钟。不同方案中脑组织因渗透作用引起的水分流失仅为理想渗透行为预测值的26%-78%，这表明存在一定程度的组织体积调节，并且脑内钠、氯和钾含量增加。这种增加足以在高钠血症120分钟时定量解释组织体积调节，但在较短时间或甘露醇或蔗糖诱导的高渗状态下则不然。水分流失和电解质摄取在30分钟内同时发生，这限制了脑萎缩的程度。对急性高渗状态下组织电解质增加的时间进程和幅度的分析结果，分别构成了以下两项关于血浆和脑脊液中电解质体积调节性内流研究的基础。
