Umod−/− mice (uromodulin deficiency) display a urine concentrating defect, polyuria, salt wasting, low BP, low eGFR and a compensatory upregulation of distal tubular sodium transporters (some misplaced in the cytoplasm, like NKCC2 and NCC, rather than in the apical membrane) [91, 92]. The gene discussed is UMOD; the disease is hyperinsulinemic hypoglycemia, familial, 4.