RAAS

Question 1

What does the RAAS do

Answer 1

Helps to maintain blood pressure - over hours - days.

Question 2

1st 4 steps in RAAS

Answer 2

Decrease in BP

Less stretch results in the release of renin from Afferent arteriole

Renin converts Angiotensinogen (from liver) to Angiotensin 1

ACE converts Angiotensin 1 to Angiotensin 2

Question 3

What does Angiotensin 2 do

Answer 3

Stimulates SNS

Vasoconstriction of arterioles

Increases Na, K, Cl reabsorption in proximal tubule (Active Transport) and Passive transport of H2O

Signals Posterior Pituitary gland to release ADH

Signals Adrenal cortex to release Aldosterone

Question 4

What does Posterior Pituitary release

What does this hormone do

Answer 4

Releases ADH

Stimulates thirst

Increases permeability in distal tubule to increase water reabsorption

Question 5

What does Aldosterone do

Answer 5

Aldosterone assists Angiotensin 2 in the proximal tubule to increase active transport Na, K, Ca and passive transport of H2O.

Vasoconstriction

Question 6

Final step in RAAS

Answer 6

Increased BP results in stretching of the AFFERENT arterioles in the Glomerular Apparatus and decreases renin release.