Epithelial Na+ Channels, Immune Cells, and Salt.

Epithelial Na+ channels (ENaCs) are known to affect blood pressure through their role in transporting Na+ in the distal nephron of the kidney. While expressed in other epithelial tissues, there is growing evidence that ENaCs are also expressed in nonepithelial tissues where their activity influences blood pressure. This review provides an overview of ENaCs and key mechanisms that regulate channel activity. The role of ENaCs in antigen-presenting dendritic cells is discussed, where ENaC-dependent sensing of increases in the extracellular Na+ concentration leads to activation of a signaling cascade, T cell activation with the release of proinflammatory cytokines, and an increase in blood pressure. The potential contribution of this pathway to human hypertension is discussed.