21. Diuretics & RAAS Antagonists Flashcards
Although the Na+-K+-2Cl- cotransporter (NKCC2) is electrically neutral, its action leads to excess intracellular K+ which then back diffuses into lumen creating a lumen positive potential. This potential then drives the reabsorption of _____.
cations Mg++ and Ca++
What is aldosterone?
major mineralocorticoid- Na+ sparing, K+ wasting
Inhibition of CA by ______ results in retention of HCO3- in lumen (urine) with mild alkaline diuresis.
acetazolamide
_____ diuretics are the most efficacious.
Loop
Water removal (from lumen) occurs in descending limb as a result of _____ generated in interstitial spaces.
hypertonic osmotic forces
What are some important SEs for spironolactone?
gynocomastia, hyperkalemia
_____ inhibit the Na+/Cl- cotransporter, causing increased urinary secretion of NaCl.
Thiazide diuretics
Tx with loop diuretics and thiazides causes increased plasma concentrations of uric acid, possibly leading to ____.
gout
Most Na+ comes back in at the proximal convoluted tubule, and ____ don’t affect that.
diuretics
Thiazide diuretics inhibit the Na+/Cl- cotransporter, causing increased urinary secretion of _____.
NaCl
Thiazide diuretics inhibit the _____, causing increased urinary secretion of NaCl.
Na+/Cl- cotransporter
Inhibition of the _____ enzyme depresses NaHCO3 reabsorption in proximal tubule.
carbonic anhydrase
What is the consequence of hypokalemia?
more ectopic pacemakers
What is the major extracellular cation?
Na+
_____, a diuretic, works by interacting with hormone receptors.
Spironolactone
The major use of aldosterone antagonists in HF, even though they are diuretics, is as ____.
an anti-remodeling agent
Nearly all diuretic agents exert their effects at _____ surface of renal tubule cells.
luminal (urine)
Name a diuretic used to treat HF.
Furosemide
Active NaCl reabsorption occurs in the _____ via the Na+-K+-2Cl- cotransporter (NKCC2).
ascending limb
Active NaCl reabsorption occurs in ascending limb via the _____.
Na+-K+-2Cl- cotransporter (NKCC2)
Inhibition of the carbonic anhydrase enzyme depresses NaHCO3 reabsorption in the _____.
proximal tubule
Name 3 Carbonic Anhydrase Inhibitors.
- Acetazolamide (Diamox) 2. Dorzolamide 3. Brinzolamide
Anti-remodeling occurs by decreasing ____, ____, and _____.
hypertrophy, fibrosis, apoptosis
When can furosemide be started?
either acutely or chronically
Which 2 classes of drugs have anti-remodeling action and are assoc. with decreases in morbidity/mortality?
- Beta-blockers (beta-1 receptor) 2. ARBs (angiotensin-II receptor)
Which diuretic has a SE of ototoxicity?
ethacrynic acid
What is the most common s/s for diuretic OD?
dizziness upon standing