Shiraki K, Hong S K, Park Y S, Sagawa S, Konda N, Claybaugh J R, Takeuchi H, Matsui N, Nakayama H
School of Medicine, University of Occupational and Environmental Health, Kitakyushu, Japan.
Undersea Biomed Res. 1987 Sep;14(5):387-400.
Four male divers were exposed to a dry, 31 ATA, He-O2 environment for 7 d (Seadragon VI). Urine was collected diurnally (0700-2200 h) and nocturnally (2200-0700 h) before (predive 1 ATA air), during, and after (decompression and postdive 1 ATA air) exposure to 31 ATA. A typical hyperbaric diuresis associated with a reduction in urine osmolality was observed in the face of a constant creatinine clearance. A significant increase (P less than 0.05) in osmolal clearance (COSM) was observed with concomitant decrease (P less than 0.05) in negative free water clearance, indicating that the diuresis has both osmotic and free water components. Although urine flow increased at pressure during both day and night, its magnitude was twofold greater at night as compared to daytime. Moreover, the diurnal diuresis was entirely due to an increase in free water excretion, whereas the nocturnal diuresis was largely due to an increased COSM. These results indicate that hyperbaric diuresis is induced by inhibition of tubular reabsorption of free water during daytime and of certain solutes during the night. Approximately 80% of the nocturnal increase in the excretion of osmotic substances was accounted for by Na, K, Cl, and urea.
四名男性潜水员在31个绝对大气压的干燥氦氧环境中暴露7天（海龙六号）。在暴露于31个绝对大气压之前（潜水前1个绝对大气压空气环境）、期间和之后（减压和潜水后1个绝对大气压空气环境），每日（07:00-22:00）和夜间（22:00-07:00）收集尿液。在肌酐清除率恒定的情况下，观察到了与尿渗透压降低相关的典型高压利尿现象。随着负自由水清除率的降低（P<0.05），渗透清除率（COSM）显著增加（P<0.05），这表明利尿既有渗透成分又有自由水成分。尽管白天和夜间在压力下尿流量均增加，但其夜间增加幅度是白天的两倍。此外，日间利尿完全是由于自由水排泄增加，而夜间利尿主要是由于COSM增加。这些结果表明，高压利尿是由白天肾小管对自由水重吸收的抑制以及夜间对某些溶质重吸收的抑制所诱导的。夜间渗透物质排泄增加量的约80%由钠、钾、氯和尿素构成。
