Diuretics Flashcards
What does a natriuretic do?
Increases Na+ excretion
What does a kaliuretic do?
Increases K+ excretion
What does a aquauretic do?
Increased water excretion
What is the most important hormone regulating water balance?
ADH
What can cause ADH levels to change?
Alcohol
Nicotine
Where do loop diuretics act?
Thick ascending limb of LoH
Where do loop diuretics act?
Thick ascending limb of LoH
Where do thiazide diuretics act?
Distal tubule
Where do potassium sparing diuretics act?
Distal tubule
Collecting ducts
What is the molecular action of loop diuretics?
Blockage Cl- channel of Na/K/2Cl co-transporter in thick ascending limb of LoH
Where to loop diuretics increase Na+ delivery to?
Distal tubule → exchanged for K+ → excreted in urine
What is the molecular action of thiazide diuretics?
Blockade of apical Na/Cl co-transported in DCT
What is the molecular action of thiazide like diuretics?
Activates Katp channel In smooth muscle of blood vessels to dilate arterioles
What is the molecular action of aldosterone antagonists?
Block upregulation of Na+ channels in DCT by aldosterone.
Is Spironolactone a pro drug or active drug?
Pro drug
Metabolised to active form Canrenone
What is spironolactone structurally similar to?
Oestrogen
What is an example of a potassium sparing diuretic?
Amiloride
Used in combination with loop diuretics
What is the molecular action of potassium sparing diuretics?
Direct inhibitor of epithelial Na+ channels (ENC) in DCT
What are osmotic diuretics?
Non-re-absorbable solute.
Undergoes glomerular filtration
Increase in water in circulating plasma and in urine by osmosis
