CFTR and Salla disease: Aside from CFTR, other ion transporters suitable as drug targets in SD include the apical Na+/H+ exchanger NHE3, the basolateral Cl− importer NKCC1, and the basolateral K+ channels KCNQ1 and KCNN4, which hyperpolarize the cell membrane and enhance the electrical driving force for Cl− exit through the CFTR channel [73].