Opening lines of communication in the distal nephron.

The distal nephron is composed of two main cell types: principal cells and intercalated cells. These cells have distinct morphologic features that allow them to be readily distinguished by light microscopy, as well as distinct suites of proteins that facilitate cell-specific transport properties. In this issue of the JCI, Gueutin and colleagues describe a new mechanism by which β-intercalated cells, via release of ATP and prostaglandin E2 (PGE2), influence the activity of transporters in principal cells.