Mutations in α, β, or γ subunits of the epithelial sodium channel (ENaC) can downregulate
ENaC activity and cause a severe salt-losing syndrome with hyperkalemia and metabolic
acidosis, designated pseudohypoaldosteronism type 1 in humans. In contrast, mice with
selective inactivation of αENaC in the collecting duct (CD) maintain sodium and potassium
balance, suggesting that the late distal convoluted tubule (DCT2) and/or the connecting
tubule (CNT) participates in sodium homeostasis. To investigate the relative importance of …