Diuretics and RAAS Antagonists

Question 1

Nitrates dilate the _________ and hydralazine dilates the _________.

Answer 1

veins; arteries

Question 2

Why do ACE inhibitors and aldosterone-receptor antagonists cause hyperkalemia?

Answer 2

Because aldosterone lowers serum potassium levels, so blocking its action leads to hyperkalemia

Question 3

Low serum potassium leads to _________ conductance.

Answer 3

decreased

Question 4

High serum potassium leads to _________ conductance.

Answer 4

increased

Question 5

Hypokalemia can lead to _____________ in the heart.

Answer 5

U waves and ectopic pacemakers

Question 6

The most worrisome side effect of loop diuretics is ___________.

Answer 6

hypokalemia

Question 7

There are two classes of potassium-sparing diuretics: _____________.

Answer 7

aldosterone-receptor antagonists and collecting tubule sodium channel blockers

Question 8

Sprionolactone is an _____________.

Answer 8

aldosterone receptor antagonist

Question 9

Some people have endocrine effects with spironolactone, so ________ is used instead.

Answer 9

eplerenone

Question 10

Loop diuretics like furosemide act on the ____________ division of the loop of Henle.

Answer 10

ascending

Question 11

Aldosterone is a __________ that acts on the _________ part of the kidney.

Answer 11

hormone; collecting duct

Question 12

Thiazides work on the ______________.

Answer 12

distal convoluted tubule

Question 13

Excess intracellular potassium ions in the cells of the ascending loop leads to a potential that ____________.

Answer 13

drives the entry of magnesium and calcium ions

Question 14

Because furosemide inhibits the Na/KCl pump–which then decreases the potassium potential–one side effect of furosemide and other loop diuretics is ____________.

Answer 14

hypomegnesemia and hypocalcemia, because the potassium potential is needed to drive the entry of these ions from the lumen to the intracellular environment

Question 15

__________ can ameliorate potassium wasting.

Answer 15

Aldosterone antagonists

Question 16

In contrast to loop diuretics, thiazide works by ____________.

Answer 16

inhibiting the NaCl symporter; this drives the NCX on the basolateral side of the cell to pump calcium into the blood and sodium into the cell, thus increasing calcium absorption

Question 17

Thiazides can precipitate a gouty attack, because they ___________.

Answer 17

compete for the same organic acid secretory system as uric acid, thus raising uric acid levels

Question 18

Aldosterone stimulates a receptor in the collecting tubule that _____________.

Answer 18

resorbs sodium and expels potassium; thus, inhibiting this transporter causes excretion of sodium and increased retention of potassium

Question 19

_________ also decrease bradykinin activation, further enhancing vasodilation.

Answer 19

ACE inhibitors

Question 20

All ACE inhibitors are administered as _________.

Answer 20

prodrugs that get activated by the liver, except lisinopril and captopril

Question 21

Ibuprofen and naproxen have the potential to ___________.

Answer 21

exacerbate heart problems

Question 22

What are the three main goals of pharmacologic heart-failure management?

Answer 22

Reduce congestion, improve flow, and modulate neurohormonal activation

Question 23

All heart failure patients need to take __________, but only more some will take __________, depending on symptoms.

Answer 23

ACE inhibitors and ß-blockers; ARBs, vasodilators, or diuretics

Question 24

Angiotensin receptor blockers (ARBs) are used in patients intolerant to ___________.

Answer 24

ACE inhibitors

Question 25

The effect of serum potassium on conductance is paradoxical: low potassium leads to _________, while high potassium leads to ___________.

Answer 25

decreased conductance (because of increased electrochemical potential); increased conductance (because of decreased electrochemical potential)

Question 26

What levels of potassium lead to increased ectopic arrhytmogenesis?

Answer 26

Hypokalemia

Question 27

Hyperkalemia leads to ________ heart rate.

Answer 27

bradycardiac (because of decreased conductance)

Question 28

People who are hypokalemic should not be given drugs that __________ heart rate.

Answer 28

increase

Question 29

What is the mechanism for thiazide-induced hypokalemia?

Answer 29

It increases the luminal concentration of sodium in the distal convoluted tubule, thus causing more Na/K exchange in the collecting tubule.

Question 30

_________ can cause hyperkalemia when given with ACE inhibitors.

Answer 30

Aldosterone receptor antagonists

Question 31

ACE inhibitors also inhibit __________, further increasing their vasodilator effects.

Answer 31

bradykinin

Question 32

Losartan is the only angiotensin II receptor antagonist that is dosed __________.

Answer 32

twice daily

Question 33

Decreased losartan dose is necessary in ______ dysfunction.

Answer 33

hepatic