Anti-Diuretic Hormone Flashcards
ADH (anti-diuretic hormone) is synthesised in the hypothalamus & is stored in the posterior pituitary gland. What is its role?
ADH is responsible for osmoregulation - regulating water balance in the body. It also contains osmoreceptors which detects osmolarity changes of the blood.
Describe what low osmolarity means
Low solute, high water - osmoreceptors are not activated & ADH secretion is suppressed. Very little ADH is produced & almost no water is reabsorbed, meaning a large volume of dilute urine is produced.
Describe what high osmolarity means
High solute, low water - osmoreceptors stimulate the neurons of the hypothalamus. Low water concentration means a lot of ADH is produced & the kidney tubules become more permeable. Lots of water is absorbed into the bloodstream, meaning only a small volume of concentrated urine is produced.
Electrical signals from the neurons then stimulate release of ADH into the bloodstream. The response causes the kidney tubules to become more permeable & increase water reabsorption.
