21. Diuretics & RAAS Antagonists Flashcards
Almost all of glucose, amino acids, NaHCO3, and other metabolites are reabsorbed in the _____.
proximal convoluted tubule
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
Water removal (from lumen) occurs in the _____ as a result of hypertonic osmotic forces generated in interstitial spaces.
descending limb
Although the _____ 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++.
Na+-K+-2Cl- cotransporter (NKCC2)
Tx with loop diuretics and thiazides causes increased plasma concentrations of uric acid, possibly leading to ____.
gout
_____ inhibit the Na+/Cl- cotransporter, causing increased urinary secretion of NaCl.
Thiazide diuretics
How are neurohormones modulated?
RAAS antagonists and Beta-blockers
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
Inhibition of the carbonic anhydrase enzyme depresses NaHCO3 reabsorption in the _____.
proximal tubule
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 major extracellular cation?
Na+
What is the consequence of hypokalemia?
more ectopic pacemakers
_____, a diuretic, works by interacting with hormone receptors.
Spironolactone
Nearly all diuretic agents exert their effects at _____ surface of renal tubule cells.
luminal (urine)
The major use of aldosterone antagonists in HF, even though they are diuretics, is as ____.
an anti-remodeling agent
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)
Name 3 Carbonic Anhydrase Inhibitors.
- Acetazolamide (Diamox) 2. Dorzolamide 3. Brinzolamide
What is the consequence of hyperkalemia?
conduction block disorders
Aldosterone antagonists tend to be _____.
K+ sparing
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
The _____ decrease Na+ reabsorption, so increased Na+ and water enter the urine.
diuretic agents
Almost all of _____, _____, _____, and _____ are reabsorbed in the proximal convoluted tubule.
glucose; amino acids; NaHCO3; other metabolites
Sometimes loop diuretics are augmented with a _____.
thiazide diuretic
What is the common name for furosemide?
Lasix
Inhibition of CA by acetazolamide results in retention of HCO3- in lumen (urine) with ______.
mild alkaline diuresis
How is congestion reduced?
diuretics
____ works via osmotic effects that prevent water reabsorption.
Mannitol
Are diuretics used chronically or acutely?
both
Water removal (from lumen) occurs in descending limb as a result of _____ generated in interstitial spaces.
hypertonic osmotic forces
Although the Na+-K+-2Cl- cotransporter (NKCC2) is electrically neutral, its action leads to excess _____ which then back diffuses into the lumen, creating a lumen positive potential. This potential then drives the reabsorption of cations Mg++ and Ca++.
intracellular K+
_____ tend to be K+ sparing.
Aldosterone antagonists
Water removal (from lumen) occurs in the _____ as a result of hypertonic osmotic forces generated in interstitial spaces.
descending limb
ACE inhibitors indirectly block the release of aldosterone, so they are _____.
K+ sparing
What are the K+ sparing diuretics?
Na+ channel blockers and aldosterone antagonists
Name 3 goals of heart failure management with pharmacotherapy.
- reduction of congestion 2. modulate neurohormonal regulation 3. improve flow
What are K+ sparing diuretics used for?
anti-fibrotics
A true synergistic effect may be achieved with a ____ and a ____ in refractory edema.
thiazide; loop diuretic
What diuretic works by inhibiting Na+-K+-ATPase?
none
Thiazides increase reabsorption of ____, but loop diuretics decrease serum _____ levels.
Ca++; Ca++
Nearly all diuretic agents exert their effects at luminal (urine) surface of _____.
renal tubule cells
What is often the first tx for HF?
Furosemide
How is flow improved?
vasodilators (difficult- usu req mechanical devices or transplantation)
_____increase reabsorption of Ca++, but _____ decrease serum Ca++ levels.
Thiazides; loop diuretics
Most Na+ comes back in at the _____, and diuretics don’t affect that.
proximal convoluted tubule
What is another name for loop diuretics and why?
high ceiling bc they give the maximum efficacy of all diuretics
ACE inhibitors indirectly block the release of _____, so they are K+ sparing.
aldosterone
Inhibition of the carbonic anhydrase enzyme depresses ______ in proximal tubule.
NaHCO3 reabsorption
Nearly all _____ agents exert their effects at luminal (urine) surface of renal tubule cells.
diuretic
The diuretic agents decrease ______, so increased Na+ and water enter the urine.
Na+ reabsorption
Active ____ reabsorption occurs in ascending limb via the Na+-K+-2Cl- cotransporter (NKCC2).
NaCl
What is the major use of _____ in HF, even though they are diuretics, is as an anti-remodeling agent?
aldosterone antagonists
____ and ____, both diuretics, work by interacting with membrane transport proteins.
Thiazides; furosemide
Carbonic Anhydrase Inhibitors are used to treat?
Glaucoma, acute mountain sickness
What are some SEs for the thiazides?
hypokalemia hyperglycemia gout hyperlipidemia 2a hyperaldosteronism allergic rxns
Loop diuretic efficacy is increased with ____.
dietary salt restriction (
