THE SIGNIFICANCE OF THE SODIUM AND POTASSIUM CONTENT OF MUSCLE TISSUE AND THE RELATION OF THE AMOUNT OF EDEMA FLUID IN MUSCLE TO THE LEVEL OF SERUM PROTEIN IN EXPERIMENTAL NUTRITIONAL EDEMA

Abstract

On the basis of Na, K and water detns. in edematous muscles from rats with varying degrees of nutritional edema the amts. of extracellular fluid were calculated with the use of the assumptions that all Na is in the extracellular fluid and that its concn. in this fluid is equal to that detd. in the free edema fluids found in some of the rats. The concns. of K in intracellular water and of Na + K in total water, derived from the above data for edematous rats, were found to be the same, within physiological variation, as these same concns. derived in the same way for normal rats. The theory, then, that the accumulation of fluid in the tissues in conditions of hypoproteinemia was simply a result of ultrafiltration through the capillaries caused by the reduced plasma oncotic pressure was compatible with these detns. of the predominant bases in edematous rat muscles. Serum protein detns. correlated with the extracellular fluid figures in the muscle tissue indicated that there was no "critical level" of serum, total protein or albumin for the first accumulation of edema fluid but rather that this retention began with the first loss of serum protein and progressed with increasing hypoproteinemia.