ADH & Diuretics - Trachte Flashcards Preview

CRRAB II Week 2 - WLB > ADH & Diuretics - Trachte > Flashcards

Flashcards in ADH & Diuretics - Trachte Deck (25):
1

What is the mechanism of ADH?

  • Stimulate G-protein coupled receptor (Gs) in collecting duct
  • Upregulate cAMP
  • Recruit aquaporin channels to incorporate into luminal plasma membrane
    • water moves by osmosis and gets reabsorbed in peritubular capillaries

2

What effect does ADH have on urine flow?

Decreased urine flow

(ANTI-diuretic hormone => decreased diuresis)

3

What effect does ADH have on ion concentrations?

  • Decreased [ion] in blood/serum
  • Increased [ion] in urine

4

Where do loop diuretics act in the nephron?

thick ascending limb

5

Where do thiazide diuretics act in the nephron?

distal convoluted tubule

6

Where do potassium-sparing diuretics act in the nephron?

collecting duct

7

Where do osmotic diuretics act in the nephron?

proximal tubule and/or descending limb of the loop of Henle

8

Where do Sodium-Glucose Transport Inhibitors (SGLT-2) act in the nephron?

Proximal tubule

9

Where do carbonic anhydrase inhibitors act in the neprhon?

proximal tubule

10

What diuretic(s) inhibits the Na, K, 2Cl pump in the thick ascending limb of the loop of Henle?

Furosemide (Lasix) and Bumetanide

11

What is the influence of Furosemide (Lasix) & Bumetanide on urine flow and ion concentrations in the urine?

  • Prevent decrease in osmolarity
    • results in greater retention of ions and water in later segments of the nephron
  • Increase NaCl excretion
  • Increase K+ excretion

12

What diuretics block the NaCl transporter in the distal convoluted tubule?

  • Chlorthalidone
  • Hydrochlorothiazide
  • Metalazone

13

What is the influence of HCTZ, Chlorthalidone, & Metalazone on urine flow and ion concentrations in the urine?

  • Increased excretion of water, Na+, Cl-, and K+ in the urine
    • K+ gets excreted because some of the increased Na+ is exchanged for K+ in the collecting tubule

14

What diuretics inhibit aldosterone receptors in the collecting duct?

Spironolactone & Eplerenone

15

What diuretics inhibit the Na+ exchange (ENaC) for K+ and H+ in the collecting duct?

Amiloride & Triamterene

16

What is the influence of Spironolactone, Amiloride, & Triamterene on urine flow and ion concentrations in the urine?

  • Less potassium is excreted
    • due to blocking the exchange of intraluminal Na+ for extraluminal K+ in collecting duct

17

What type of diuretic is Mannitol?

Osmotic diuretic

18

What diuretic blocks the Na+/Glucose symporter in the proximal tubule?

Canigliflozin, Dapagliflozin, Gliflozin

(–flozin)

19

What diuretic is a major carbonic anhydrase inhibitor?

Acetazolamide

20

What is the influence of Acetazolamide on urine flow and ion concentrations in the urine?

  • Urinary alkalinization
  • Produces metabolic acidosis

21

What is the major side effect of thiazide diuretics?

  • Hyperglycemia
    • thiazides bind SUR on potassium channels that control insulin release
    • opens potassium channels
    • K+ influx => hyperpolarizes ß-cells in pancreas
      • results in suppressed insulin release!

 

***Also predisposes pts. to gout. 

22

What is the influence of Mannitol on urine flow and ion concentrations in the urine?

  • Reduced water reabsorption
    • increased urine flow
    • decreased [ion]

23

What are the drugs suppress uric acid reabsorption by blocking organic anion transporters (OAT) and URAT1 in the proximal tubule?

Probenicid & Sulfinpyrazone

24

What is the name of the naturally occurring hormone that is antidiuretic?

Vasopressin

25

What is the name of the synthetic cogener of ADH?

Desmopressin