AVP and Hyponatremia: In the patient with RSW (Figure 3b), however, an isotonic saline infusion eliminated the volume stimulus for ADH secretion and allowed the coexisting hypo-osmolality to inhibit the ADH secretion to an undetectable level when the urine was dilute 13 h after initiating the isotonic saline infusions and correction of hyponatremia in 48 h [4].