Agostoni E, Zocchi L
Istituto di Fisiologia Umana I, Università di Milano, Italy.
Respir Physiol. 1993 Apr;92(1):101-13. doi: 10.1016/0034-5687(93)90123-r.
The net rate of liquid flow and Na+ flux across the pleura was determined in anesthetised rabbit during hydrothoraces 0.5 to 5 ml in size, without and with amiloride. In the hydrothoraces with amiloride the net liquid flow and Na+ flux reversed when the volume injected approached zero. This indicates that the active Na+ transport and the consequent liquid absorption occur also under physiological conditions. The difference between the data obtained without and with amiloride provides the net solute-coupled liquid outflow and active Na+ efflux. These parameters increased linearly with the hydrothorax size up to 2 ml (0.39 ml/h and 54 muEq/h, respectively), and then levelled off. The linear relationship allowed their extrapolation to physiological conditions: 0.15 ml/h (0.07 ml.h-1.kg-1) and 21 muEq/h (0.1 muEq.h-1.cm-2). The increase in these parameters with the hydrothorax size seems due to the protein dilution caused by the Ringer injection, because it did not occur if Ringer was added with albumin to keep the protein concentration in the pleural liquid similar to that under physiological conditions.
在麻醉兔身上，于胸腔积液量为0.5至5毫升时，分别在未使用和使用氨氯吡咪的情况下，测定了液体跨胸膜的净流动速率和Na⁺通量。在使用氨氯吡咪的胸腔积液中，当注入的液体量接近零时，净液体流动和Na⁺通量发生逆转。这表明在生理条件下也会发生主动Na⁺转运以及随之而来的液体吸收。未使用和使用氨氯吡咪时获得的数据差异提供了净溶质偶联液体流出和主动Na⁺外流。这些参数随着胸腔积液量增加至2毫升呈线性增加（分别为0.39毫升/小时和54微当量/小时），然后趋于平稳。这种线性关系使得可以将其外推至生理条件：0.15毫升/小时（0.07毫升·小时⁻¹·千克⁻¹）和21微当量/小时（0.1微当量·小时⁻¹·厘米⁻²）。这些参数随胸腔积液量的增加似乎是由于林格液注射导致的蛋白质稀释所致，因为如果在林格液中加入白蛋白以使胸膜液中的蛋白质浓度与生理条件下相似，这种情况就不会发生。
