Kirkebo A, Tyssebotn I
Acta Physiol Scand. 1977 Nov;101(3):257-63. doi: 10.1111/j.1748-1716.1977.tb06006.x.
The effect of dehydration on intrarenal blood flow was investigated in 11 dogs, using polarographic determination of H2-gas desaturation for measuring local blood flow in inner cortex (ICF) and outer cortex (OCF). Dehydration was induced by 48 h water deprivation +2-300 mg ethacrynic acid (EA) per os the day before the experiment. Compared to a control group (n=9) ICF was markedly reduced to 2.40 +/- 0.47 ml/min X g (control 3.23 +/- 0.64) whereas OCF 3.29 +/- 0.80 ml/min X g was nearly unchanged (control 3.59 +/- 0.85). The ratio OCF/ICF was increased to 1.37 (1.11). Further dehydration by hypertonic peritoneal dialysis for 3 h increased Hct to 60 +/- 4 and further reduced OCF and ICF, without significant change of the OCF/ICF-ratio. At Hct above 55 sudden and intermittent changes in local cortical blood flow were recorded randomly at individual electrode sites, showing ischemic periods lasting for 1 to 60 min. Such flow changes were observed in 13 of 14 expts. and were not accompanied by changes in RBF. It is concluded that moderate dehydration causes a greater reduction of ICF than of OCF. Severe dehydration gives in addition rise to patchy, intermittent ischemia in both cortical layers.
采用极谱法测定氢气去饱和作用来测量11只狗肾内血流，以研究脱水对肾内血流的影响，该方法用于测量肾内皮质（ICF）和肾外皮质（OCF）的局部血流。在实验前一天，通过48小时禁水+口服2 - 300毫克依他尼酸（EA）诱导脱水。与对照组（n = 9）相比，ICF显著降低至2.40±0.47毫升/分钟×克（对照组为3.23±0.64），而OCF为3.29±0.80毫升/分钟×克，几乎未变（对照组为3.59±0.85）。OCF/ICF比值增至1.37（1.11）。通过高渗腹膜透析进一步脱水3小时使血细胞比容（Hct）升至60±4，并进一步降低了OCF和ICF，但OCF/ICF比值无显著变化。当Hct高于55时，在各个电极部位随机记录到局部皮质血流突然且间歇性的变化，显示缺血期持续1至60分钟。在14次实验中的13次观察到了这种血流变化，且未伴有肾血流量（RBF）的变化。结论是，中度脱水导致ICF的降低幅度大于OCF。严重脱水还会在两个皮质层引发散在的、间歇性缺血。
