K+ sparing Diuretics Flashcards
what is the site of action of K+ sparing Diuretics ?
Collecting Duct
what are the two types of cells found in the collecting ducts ?
Principal cells
the main Na+ reabsorbing cells and the site of action of aldosterone, K+-sparing diuretics, and spironolactone.
they secrete K+ through an apical membrane potasium channel.
α-intercalated cells
cells which contain apical H+ ATPase, explaining its ability to secrete protons.
Name the K+ sparing Diuretics
Amiloride
(“Almonds”)
Triamterene
(“Tangerines”)
Eplerenone
(“apple with the teacher”)
Spironolactone
(“inspector with spiral bound notebook”)
Aldosterone MOA
- upregulates ENaCs on the apical membrane
- upregulates Na+/K+ ATPse on the basolateral membrane
- upregulates K+ channels on the apical membrane
- upregulates H+ ATPase apical membrane
K+ sparing Diuretics MOA
Amiloride , Triamterene
ENaC inhibition
Spironolactone , Eplerenone
Aldosterone receptor antagonists
what are Amiloride and Triamterene used for ?
-useful in treatment of Li+ induced nephrogenic Diabetes insipidus
(“inspidus fountain in the background”)
-Amiloride and Triamterene are useful in the treatment of Liddles syndrome (overactive ENaCs)
(“Little midget blocked by tangerines and almonds carts”)
what can Spironolactone and Eplerenone be used for ?
-useful in the treatment of primary and secondary Hyperaldosteronism, Conn syndrome, ACTH
(“Crumbling Mineral Mountain in the background”)
- useful in the treatment of heart failure to prevent K+ wasting
- prevent myocardial remodeling induced by high level of aldosterone
at higher doses Spironolactone can ..
-is a synthetic steroid inhibit Androgen receptors , more specifically 17-alpha Hydroxylase enzyme thus lowers testosterone levels in the body
(“17 alpha-fry-droxylase” “fried male symbol)
- may treat symptoms of androgen excess in PCOS such as Hirsutism (“bubbling ovary fryers”)
what are the side effects seen with K+ sparing diuretics therapy ?
-can cause mild or even dangerous hyperkalemia
(“Elevated banana’s in stand”)
-may cause a normal anion gap metabolic acidosis
(by decreasing the function of the H+ATPase)
- K+ sparing diuretics inhibit the effects of aldosterone in the collecting duct causing a **type 4 renal tubular acidosis → **only one associated with hyperkalemia**.
- **
possible side effects of Spironolactone
- inhibits androgen receptors and 17-alpha hydroxylase enzyme
- Gynecomastia (“hairy dudismo with lids on chest”)
- impotence and decreased libido (“Droopy churro”)
What are two classes of diuretics which prevent cardiac remodeling and improve outcomes in heart failure?
(1) Aldosterone receptor antagonists
- Spironolactone
- Eplerenone
(2) ACE Inhibitors
- Capto , Lisino, Rami , Enala - PRIL