SLC4A8 and Hypokalemia: Double knockout of Ncc and NDCBE, on the other side, induces a mild increase in Na+ and Cl- excretion relative to Ncc-KO, but severe hypokalemia (27), suggesting reabsorption of Na+ by principal cells, and Cl- reabsorption by B-IC are efficient in preserving NaCl in Ncc-NDCBE-KO models, but the increased electrogenic Na+ reabsorption by ENaC, associated to electroneutral Cl- reabsorption by pendrin, results in severe K+ loss due to increased driving for K+ secretion.