MEDICAL PHYSIOLOGY

Detailed explanation-1: -Vasopressin increases the water permeability of the renal collecting duct cells, allowing more water to be reabsorbed from collecting duct urine to blood.

Detailed explanation-2: -ADH increases the permeability to water of the distal convoluted tubule and collecting duct, which are normally impermeable to water. This effect causes increased water reabsorption and retention and decreases the volume of urine produced relative to its ion content.

Detailed explanation-3: -proteinuria. Causes the cells of the distal and collecting tubule to become more permeable to water; water flows into the interstitial fluid and urine volume decreases.

Detailed explanation-4: -The main role of the collecting duct is the reabsorption of water, through the action of anti-diuretic hormone (ADH) and aquaporins. ADH is produced in the hypothalamus, and stored in the posterior pituitary gland until it is released.