Final answer:
The release of antidiuretic hormone (ADH) promotes water reabsorption in the kidneys, while the stimulation of thirst leads to increased fluid consumption, both of which are mechanisms to maintain blood volume and pressure.
Step-by-step explanation:
The release of antidiuretic hormone (ADH), which stimulates the kidneys to increase water reabsorption, also stimulates thirst, which increases fluid consumption to help maintain plasma volume and thus blood pressure.
When the body needs to increase blood volume and pressure, the renin-angiotensin system plays a crucial role. This system leads to the production of angiotensin II, a potent vasoconstrictor that not only increases blood pressure directly but also triggers the release of ADH and aldosterone. ADH functions to increase water reabsorption in the kidneys, while aldosterone enhances sodium reabsorption. Water follows sodium into the blood, further aiding in the elevation of plasma volume and blood pressure. These hormonal responses also stimulate thirst through the action of angiotensin II on the hypothalamus, promoting fluid intake and contributing to the raise in blood volume and pressure.