Final answer:
The hypothalamus prompts the release of antidiuretic hormone (ADH) from the pituitary gland to increase water reabsorption in the kidneys and elevate blood pressure when detecting a high salt concentration in the blood.
Step-by-step explanation:
When the hypothalamus detects a high concentration of salt in the blood, it stimulates the pituitary gland to release antidiuretic hormone (ADH) which stimulates the kidneys to reabsorb more water and increase blood pressure.
The hormone released by the pituitary gland when the hypothalamus detects high blood salt concentration is antidiuretic hormone (ADH).
The hypothalamus senses changes in blood osmolarity, such as when there's a high concentration of salt. This triggers the release of ADH from the posterior pituitary gland. ADH travels in the blood to the kidneys, where it increases the permeability of kidney tubules to water by stimulating the insertion of water channels called aquaporins. As a result, more water is reabsorbed into the bloodstream, urine volume decreases, and blood pressure rises. When blood osmolarity returns to normal, a negative feedback mechanism reduces ADH secretion to maintain fluid balance.