镁是细胞内主要阳离子之一。其细胞外液含量仅占总体镁的1%,其中约30%与蛋白质结合。总体镁的60%以不溶形式存于骨髂,20%在骨骼肌,其余在心、肝等组织。目前,血清镁浓度测定(正常值0.75～1.25 Magnesium is one of the major cations in cells. The extracellular fluid content of only 1% of the total magnesium, of which about 30% protein binding. Sixty percent of total magnesium is present in insoluble form in the bony ilium, 20% in skeletal muscle, and the rest in the heart, liver, and other tissues. At present, serum magnesium concentration determination (normal 0.75 ~ 1.25