Control of kidney

Question 1

What is ADH?

Answer 1

Antidiuretic hormone- When water levels of blood is low ADH is released by the pituitary

Question 2

What is the function of ADH?

Answer 2

• To increase permeability of distal convoluted tubule and collecting duct to water
• Regulates the amount of water reabsorbed from glomerular filtrate (Osmoregulation- maintain balance bewteen water and minerals)

Question 3

Factors that inhibit ADH release

ADH levels decrease

Answer 3

• High fluid intake
• High blood volume
• Low blood sodium levels
• Alcohol consumption

Question 4

Factors causing ADH release

ADH levels increase

Answer 4

• Low fluid intake
• Low blood volume
• High blood sodium levels
• Nicotine and morphine

Question 5

Factors causing the release of aldosterone

Answer 5

• Low blood volumes also stimulate the secretion of alderstone from the adrenal cortex
• Mediated through a complex pathway involving the hormone renin from the kidney
  (Sodium reabsorption increases, increase in water and blood volume restored)

Question 6

What happens if ADH levels decrease?

Answer 6

• Water reabsorption decreases

- Urine output increases

Question 7

What happens if ADH levels increase?

Answer 7

• Water reabsorbtion increases

- Urine output decreases

Question 8

Symptoms of diabetes insipidus (caused by lack of ADH)

Answer 8

• Extreme thirst, large amounts of urine, frequently need to urinate
• Urine output increases
• Can be treated by administrating the ADH hormone through a pill or something else

Question 9

Why does alcohol consumption cause dehydration?

Answer 9

• Increases the product of urine (urine output increases)

- Water reabsorption decreases

Question 10

Function of aldosterone

Answer 10

• A steroid hormone that helps sodium reabsorption in the distal convoluted nephron.
• Helps water movement due to osmosis (reabsorbed is DCT)
• Net result- blood volume increases and blood pressure increases)
• Aids in the conservation of sodium, secretion of potassium, water retention and to stabilize blood pressure.

Question 11

How negative feedback mechanisms regulate blood volume and urine output?

Answer 11

• Stops the release of ADH resulting in an increase in urine output