Although in these subjects the mirabegron-induced increase in membrane expression of AQP2 and NKCC2 did not result in further urine concentration compared to baseline, and this was to be expected as they were not defective in the urine concentration mechanism, these results may represent proof-of-principle that in XNDI subjects β3-AR stimulation with mirabegron, at the proper dose, could promote antidiuresis and correct, albeit partially, polyuria. Here, ADRB3 is linked to Polyuria.