How and where changes in water content of the body are detected?
The kidneys play an important role in osmoregulation, they regulate the concentration of body fluids by controlling the amount of salts and water reabsorbed from the glomerular filtrate in the kidney tubule. The process is controlled by a pituitary hormone called antidiuretic hormone (ADH). The blood may become too concentrated as a result of excessive water loss. This could be due to excessive swea ting, eating salty foods or not drinking enough water. Such a change in the concentration of the blood is detected by the hypothalamus, (a part of the brain). The hypothalamus induces the secretion of ADH by the pituitary gland, into the blood. ADH stimulates the kidneys to reabsorbs most of the water from the glomerular filtrate in the collecting duct. This water is taken back into the blood, thus diluting it back to its normal concentration. This results in small amounts of concentrated urine being produced. If the blood passing through the hypothalamus is too dilute, due to drinking larg
