Question

Describe the relationships of ADH, Na and aldosterone r/t fluid regulation of the body

Answer 1

• Antidiuretic hormone (ADH), produced by the hypothalamus and released by the posterior pituitary, causes more water to be retained by the kidneys when water levels in the body are low.
• ADH effects water retention by creating special channels for water, called aquaporins, inside the kidneys so that more water can be resorbed before it is excreted.
• When blood pressure is low, the enzyme renin is released, which cleaves the protein angiotensinogen into angiotensin I, which is further converted into angiotensin II.
• Angiotensin II signals the adrenal cortex to release aldosterone, which then increases the retention of sodium ions, enhancing the secretion of postassium ions, resulting in water retention and an increase in blood pressure.

Aldosterone:

Aldosterone is a mineralocorticoid hormone, secreted by the adrenal cortex, that regulates the balance of sodium and potassium in the body

Mineralocorticoids such as aldosterone make your kidneys reabsorb sodium, which causes water to follow. This in turn increases blood volume and blood pressure back to normal.