PATHOLOGY

Detailed explanation-1: -The release of anti-diuretic hormone from the pituitary gland into the bloodstream is controlled by a number of factors. A decrease in blood volume or low blood pressure, which occurs during dehydration or a haemorrhage, is detected by sensors (baroreceptors) in the heart and large blood vessels.

Detailed explanation-2: -ADH, also known as vasopressin, is normally secreted in response to an increase in serum osmolality (serum sodium concentration) or to maintain normal blood pressure and intravascular volume (see Chapter 158).

Detailed explanation-3: -ADH travels in the bloodstream to the kidneys. Once at the kidneys, ADH changes the kidneys to become more permeable to water by temporarily inserting water channels, aquaporins, into the kidney tubules. Water moves out of the kidney tubules through the aquaporins, reducing urine volume.