Abstract
Compartmental analysis with Na24 has been carried out in 1) 16 subjects without edema, 2) 13 patients with edema, and 3) 5 uremic patients.
Three compartment parallel model was chosen as the most suitable model for the simulation of sodium metabolism in the human beings by trial and error. The first diffusion space of Na24, which was named the functional extracellular space averaged 17.9% of body weight in the non-edematous group. The total exchangeable sodium might be divided into 1) the functional extracefular pool, 2) the rapidly exchangeable pool, and 3) the slowly exchangeable pool.
The functional extracellular space remained almost constant in edematous states, unless the renal function is markedly impaired. It is revealed that the increase of the slowly exchangeable pool in edematous state is most remarkable, and is suggested that formation of edema and ascites would serve as a reservoir to maintain the homeostasis of the most active part of the body.
