On the other hand, Morishita et al. have shown that KO mice lacking all NOS isoforms develop nephrogenic diabetes insipidus with a reduced antidiuretic response to exogenous vasopressin, accompanied by impaired renal cAMP production, a defective membrane expression of AQP2 water channel, and tubuloglomerular lesion [23]. Here, AQP2 is linked to nephrogenic diabetes insipidus.