[Magnesium and the transport system]

Magnesium is sometimes denoted as "the overlooked cation" for although it is the second most abundant intracellular cation, the study of its homeostasis and regulation has long been neglected. However, at present it is evident that magnesium plays an important intracellular regulatory role. Magnesium transport systems can be divided into two principal categories: paracellular transport systems and transmembrane transport system. Paracellular pathway plays an important role in the intestinal and renal magnesium transports. The movement of magnesium across biological membranes is discussed from the perspectives of the secondary active transport and specific magnesium channels.