Renin-Angiotensin-Aldosterone System (RAAS)

Question 1

RAAS is controlled in the ___ using the ___

Answer 1

controlled in the kidney using the juxtaglomerular apparatus/complex

Question 2

What does the juxtaglomerular complex consist of?

Answer 2

JG cells and macula densa

Question 3

Where are JG cells?

Answer 3

Afferent and efferent arterioles

Question 4

What is the function of JG cells?

Answer 4

Make and secrete renin (enzyme)

Question 5

Where is the macula densa?

Answer 5

Distal convoluted tubule between afferent and efferent arterioles

Question 6

What is the function of macula densa?

Answer 6

Stimulate JG cells to release renin, also releases NO

Question 7

What is the macula densa sensitive to?

Answer 7

• low sodium chloride
• low blood pressure
• beta adrenergic stimulation from epinephrine

Question 8

As macula densa releases nitric oxide, what is the effect?

Answer 8

Dilation of afferent arteriole

Question 9

Renin enzymatically converts ___ (from liver) to ___

Answer 9

angiotensinogen (from liver) to angiotensin I

Question 10

Where is ACE found?

Answer 10

Lungs

Question 11

ACE, in lungs, converts ___ to ___

Answer 11

Angiotensin I to angiotensin II

Question 12

What is the effect of angiotensin II on the adrenal glands?

Answer 12

Causes release of aldosterone from zona glomerulosa

Question 13

What is the effect of angiotensin II on arterioles?

Answer 13

Constricts all arterioles, especially efferent arteriole

Question 14

As the zona glomerulosa in the adrenal cortex releases aldosterone, what happens in the blood?

Answer 14

Sodium in blood serum increases

Question 15

An increase in sodium blood serum levels will trigger what organ to release what chemical?

Answer 15

Posterior pituitary releases ADH

Question 16

What are the only two things that can constrict efferent arterioles?

Answer 16

ADH and angiotensin II

Question 17

If something in a pathway is blocked, what happens to everything after it?

Answer 17

Decreases

Question 18

If something in a pathway is blocked, what happens to everything before it?

Answer 18

Increases

Question 19

What percentage of filtrate is reabsorbed?

Answer 19

99%

Question 20

What is renal vasculature hypertension?

Answer 20

High blood pressure due to renal artery stenosis

Question 21

What are four effects of ADH released by the posterior pituitary?

Answer 21

• increase in glomerular filtration rate (GFR)
• increase in blood volume
• increase in blood pressure
• decrease in urine volume

Question 22

What is the effect of nitric oxide on arterioles?

Answer 22

Dilates afferent arteriole

Question 23

Increasing renin will…

Answer 23

increase sympathetic activity and blood pressure

Question 24

Dilating the afferent arteriole does what to glomerular filtration rate?

Answer 24

Increases

Question 25

What effect does ADH have on the distal convoluted tubule and collecting duct?

Answer 25

Inserts aquaporins

Question 26

What effect does ADH have on water reabsorption?

Answer 26

Increases

Question 27

Increasing blood volume has what effect on blood pressure?

Answer 27

Increases blood pressure

Question 28

The RAAS brings blood pressure…

Answer 28

back to normal (stimulus was low blood pressure)

Question 29

Increasing glomerular filtration rate will have what effect on blood volume? What effect on urine volume?

Answer 29

Increases blood volume and decreases urine volume

Question 30

NO from macula densa will have what effects on the afferent arteriole:
compliance?
diameter?
hydrostatic pressure?
blood flow?
resistance?

Answer 30

Vasodilated, so:
* increased compliance
* increased diameter
* increased hydrostatic pressure
* increased blood flow
* decreased resistance

Question 31

Efferent arteriole is ___ due to angiotensin II.

Answer 31

constricted