ADH release from the posterior pituitary is stimulated by which process?

a. Low blood pressure sensed by barorecep-tors in the kidneys.
b. High plasma osmolarity sensed by osmo-receptors in the hypothalamus.
c. Low osmolality sensed by osmoreceptors in the kidneys.
d. High concentration of potassium sensed by chemoreceptors in the carotid body.

ANS: B
As plasma osmolality increases, osmoreceptors are stimulated, the rate of ADH secretion increas-es, more water is reabsorbed from the kidney, and the plasma is diluted back to its set point os-molality. ADH release is stimulated by high serum osmolality, not lowered blood pressure, low osmolality, or high concentrations of potassium.