Bergström J, Hultman E
Department of Renal Medicine, Karolinska Institute, Huddings University Hospital, Stockholm, Sweden.
JPEN J Parenter Enteral Nutr. 1987 Sep-Oct;11(5 Suppl):51S-54S. doi: 10.1177/014860718701100506.
Nutritional inadequacies profoundly affect the content and distribution of water and electrolytes in muscle tissue. However, most changes in tissue water and electrolytes are nonspecific and reflect the degree of sickness; they cannot be used for evaluation of malnutrition, except to indicate whether there is a loss or excess of intracellular ions, such as potassium and magnesium. In patients without disturbances in potassium metabolism, muscle cell potassium and protein are strongly correlated, but this relationship does not hold true in patients with potassium depletion. Accumulation and loss of potassium occur in parallel with changes in muscle glycogen, independent of other muscle constituents, eg, magnesium. Potassium depletion and excess, as well as changes in muscle glycogen, must be considered when evaluating the relation of lean body mass and total body protein content to total body potassium.
营养不足会深刻影响肌肉组织中水分和电解质的含量及分布。然而，组织水分和电解质的大多数变化是非特异性的，反映的是疾病的程度；它们不能用于评估营养不良，除非用于表明细胞内离子（如钾和镁）是否有丢失或过量。在钾代谢无紊乱的患者中，肌肉细胞钾与蛋白质密切相关，但这种关系在钾缺乏的患者中并不成立。钾的蓄积和丢失与肌肉糖原的变化平行发生，与其他肌肉成分（如镁）无关。在评估瘦体重和全身蛋白质含量与全身钾的关系时，必须考虑钾缺乏和过量以及肌肉糖原的变化。
