Direct effects of phosphate on vascular cell function.

Elevated serum phosphate has clinically been associated with vascular stiffness and cardiovascular mortality. Mechanistic studies over the past decade regarding local effects of phosphate on the vessel wall have provided insight into various pathways that culminate in vascular calcification. Smooth muscle cell phenotype change and apoptosis play prominent roles. The sodium-phosphate cotransporter PiT-1 is required for the osteochondrogenic differentiation of smooth muscle cells in vitro. Less is known about phosphate-driven valve interstitial cell calcification and elastin degradation. In this article, we review the current knowledge about phosphate-induced changes in the vascular wall.