Collecting Duct

Question 1

amiloride MOA

Answer 1

block Na channel in luminal membrane

Question 2

Spironolactone MOA

Answer 2

acts as competitive antagonist for cytoplasmic actions of aldosterone

Question 3

Net result of CD diuretics

Answer 3

mild increase in Na excretion

(lumen less negative potential, so K and H secretion diminished)…DECREASED K+ secretion!!!

Question 4

aldosterone antagonists

Answer 4

Spironolactone

Eplenerone

Question 5

Spironolactone

Answer 5

Aldactone
(+HCTZ=Aldactazide)

pro-drug that is extensively metabolized
canrenone is active metabolite

side effects:

• -hyperkalemia (combine w/ a thiazide)
• -Gynecomastia
• -hirsutism
• -uterine bleeding

Question 6

Eplenerone

Answer 6

Inspra

Expected to have less side effects b/c has very low affinity for androgen receptors compared to spironolactone

Clinical uses:

• -Diuretic, usually in combo w/ HCTZ
• -Treatment of CHF and cirrhosis

Question 7

K-Sparing Diuretics

Answer 7

Triametrene

Amiloride

Question 8

K-Sparing Diuretics MOA

Answer 8

Inhibit Na reabsorption in late distal tubule, (sodium load segment)

Question 9

K-sparing Diuretics effects

Answer 9

Increase urinary excretion of Na (weak effect)

Inhibit secretion of K and H (K-sparring)

Question 10

K-Sparing…clinical uses

Answer 10

Diuretics. combined w/ HCTZ (Dyazide) to increase their effectiveness and decrease K excretion

Question 11

K-Sparing…Side effects

Answer 11

Hyperkalemia

megaloblastc anemia in pts w/ cirrhosis

Question 12

Dyazide

Answer 12

1 diuretic hypertensive!!!

K-sparing diuretic + HCTZ

Question 13

Triametrene

Answer 13

Dyrenium

Question 14

Amiloride

Answer 14

Midamor