Osmoregulation of Vasopressin Secretion and Thirst	

Slow infusion of hypertonic saline into healthy individuals causes a linear increase in plasma osmolality, which in turn stimulates vasopressin release and thirst (Fig. 5.11). Conversely, a fall in plasma osmolality induced by an oral water load suppresses vasopressin secretion, with plasma concentrations becoming undetectable, and inhibits thirst.