| [ Summary ] |
Phosphorus exerts various biological functions. Recent studies have demonstrated that alterations in the levels of extracellular inorganic phosphate regulate functions in some cell types. In bone cells such as osteoblasts and chondrocytes, extracellular phosphate plays some roles in cell proliferation, differentiation, mineralization and apoptosis. In extraskeletal tissues as well, phosphate influences cell function. For example, increased extracellular phosphate results in dysfunction in vascular endothelial cells and calcification of smooth muscle cells. It is suggested that extracellular inorganic phosphate regulates cell functions partly through type III Na+/Pi cotransporter Pit-1 and Raf/MEK/ERK pathway. |