Human Phys 5.4

Question 1

Renin-Angiotensin-Aldosterone system

Answer 1

Decreased BP leads to decreased renal perfusion pressure

Renin reacts with Angiotensinogen and it is released from the liver and causes angiotensin one to be converted into angiotensin 2 by ACE

Angiotensin 2 causes increases in aldosterone, Na+ reabsorption, Na+ H+ exchange, thirst, vasoconstriction, and TPR

Leads to normal BP

Question 2

What does angiotensin 2 work through?

Answer 2

AT1 receptor

Question 3

Why does ACE breakdown bradykinin?

Answer 3

To take away vasodilation and reduces nitric oxide availability

Question 4

What is the novel RAAS pathway?

Answer 4

ACE breaks down angiotensin 2 in to angiotensin 1-7 which causes decreased vasoconstriction, increased Na+ and water excretion (lowering BP)

Question 5

What are the effects of renal artery stenosis on BP?

Answer 5

Early rise in mean arterial pressure due to the vasoconstricting effects of the RAAS system

Renin secretion is normalized because renal artery BP is normalized

Second rise in mean arterial pressure due to Na+ and water retention activity of the RAAS system

Question 6

Where are baroreceptors located?

Answer 6

Aortic arch and carotid sinus