4

Question 1

Where is Na reabsorbed in the kidney? (4)

Answer 1

1) Proximal convoluted tubule
2) Loop of Henle
3) Distal convoluted tubule
4) Collecting duct

Question 2

What do loop diuretics work on

Answer 2

Na/K/2Cl

Question 3

What do thiazides work on

Answer 3

Na/Cl

Question 4

What do K sparing diuretics

Answer 4

Na channels

Question 5

What is the proposed mechanism by which thiazide administration mediates its effect long term

Answer 5

Direct vasodilation

Question 6

What are examples of loop diuretics

Answer 6

frusemide (lasix)

bumetanide (burinex)

Question 7

What is the MOA of loop diuretics

Answer 7

Inhibits Na/K/2Cl transporter and decrease water reabsorption in the collecting duct

Question 8

What are some of the other salts that can also be lost using loop diuretics

Answer 8

MARKED DIURESIS

K, H, Ca2+ and Mg2+

Question 9

What are some clinical uses of loop diuretics

Answer 9

Oedema
Hypertension
Heart failure
Hypercalcaemia

Question 10

What is oedema

Answer 10

Swelling of a tissue that results from excessive accumulation of fluid within the tissue

Question 11

What are examples of thiazides

Answer 11

Hydrochlorothiazide (Dithiazide)

Indapamide (Natrilix or Dapatabs)

Question 12

What salts are lost from using thiazides + which salt has a decreased loss

Answer 12

MODERATE DIURESIS
Na, H2O, K and H loss
Ca2+

Question 13

Clinical uses of thiazide diuretics

Answer 13

Hypertension
Heart failure
Prevention of recurrent stone formation in idiopathic hypercalciuria

Question 14

What is the MOA of spironolactone

Answer 14

Blocks actions of aldosterone

Aldactone/Spiractin

Question 15

What is the MOA of amiloride

Answer 15

Blocks Na+ channels

component of Moduretic

Question 16

What is the effect of K+ sparing diuretics + salts lost

Answer 16

MILD DIURESIS
Decreased K+ and H+ loss
Little effect on Ca2+ and Mg2+`

Question 17

What is a clinical use of amiloride

Answer 17

Used with K+ losing diuretics to prevent K+ loss

Question 18

What is a clinical use of spironolactone

Answer 18

Hyperaldosteronism and heart failure

Question 19

What is transepithelial potential difference

Answer 19

Voltage across an epithelium

Question 20

Why do loop and thiazide diuretics cause K+ and H+ loss

Answer 20

Increased delivery of Na downstream results in increased Na+ reabsorption in LDT/CD
Increased Na+ reabsoprtion increases activity of Na/K ATPase and ive transepithelial potential difference in LDT/CD

Question 21

How do diuretics work as antihypertensives (3)

Answer 21

Decrease in extracellular fluid volume and hence blood volume
Direct vasodilatory effect
Decreased vascular reactivity (sensitivity to noradrenaline and AngII reduced)

Question 22

Which diuretic is most potent

Answer 22

Loop diuretic