Renal (diuretics) - INCOMPLETE Flashcards
What is isosmotic principle
mammalian cell membranes cannot sustain an osmotic gradient
extracellular osmolality = intracellular osmolality
What is the “60 - 40 - 20 Rule”
20% of body mass is in ECF
40% of body mass is in ICF
60% of body mass H20 in TBW
what does osmotic pressure gradients determine
intracellular vs extracellular fluid distribution
what do the Starling forces determine
intravascular vs extravascular distribution
(plasma volume vs interstitial fluid volume)
What are the general diuretic classes
osmotic
carbonic anhydrase inhibitors
loop diuretics
thiazide/thiazine-like
K+ sparing diuretics: mineralocorticoid antagonists, EMaC inhibitors
aquaretics
where is a majority of the Na+ reabsorbed within the nephron
proximal tubule
what are the osmotic diuretics
mannitol and urea
what is the MOA of osmotic diuretics
inhibit nephron H20 and solute reabsoprtion via generation of a luminally-directed osmotic pressure gradient
what is the use of Osmotic diuretics
intracranial pressure reduction (mannitol)
intraocular pressure reduction(mannitol)
hyponatremia (urea)
What are the carbonic anhydrase inhibitors
Acetazolamide
what is the MOA of carbonic anhydrase inhibitors
inhibit carbonic anhydrase activity
(sodium reabsorption and H_ secretion via apical Na/H exchange)
what is the use of carbonic anhydrase inhibitors
glaucoma
acute mountain sickness
metabolic alkalosis
urine alkalization
What are the loop diuretics
furosemide
bumetanide
torsemide
what is the MOA of loop diuretics
inhibits NA+, K+, 2Cl- co-transporter in TALH
-disrupt both diluting and concentrating ability
-luminal secretion via PT organic anion transporters
what is the use of loop diuretics
edematous states
hypercalcemia
hyponatremia
what is TALH
thick ascending loop of henle - where loop diuretics work
what are the thiazide medications
HCTZ
CTZ
metolazone
chlorthalidone
what is the use of thaizide medications
HTN
Ca urolithiasis
NDI
what is the MOA of thiazide medications
inhibit Na+, Cl- co-transporter in early DT
-affect diluting capacity, but not concentrating ability
luminal secretion via PT organic anion transporters
What are the Mineralocorticoid K+ sparing diuretics
Spironolactone, Eplerenone
what is the MOA of Mineralocorticoid K+ sparing diuretics
antagonize aldosterone action in the principe cells (late DT and CD) - inhibit Na+ reabsorption and K+ excretion
what is the use of Mineralocorticoid K+ sparing diuretics
Hyperaldosteronism
hypokalemia
HfrEF
resistant HTN
What are the ENaC inhibiting K+ sparing diuretics
Amiloride
Triamterene
what is the MOA of ENaC inhibiting K+ sparing diuretics
direct inhibition of apical Na+ uptake via ENAcC in principal cells
What are the Aqueretics (Vaptans)
Tolvaptan and Lixivaptan
what is the MOA of Aqueretics (Vaptans)
block AVP action in the late DT and CD
inhibit urine concentration by preventing AVP-stimulated AQP2 insertion into luminal membrane of principal cells (inhibits H20 abstraction in DT and CD)
what is the use of Aqueretics (Vaptans)
Hypoatremia
