5. Diuretics Flashcards
renal physiology mnemonic?
- Regulatory
- Excretory
- Endocrine
- Metabolism
renal regulatory function?
– Fluid balance
– Acid-base balance
– Electrolyte Balance
renal Excretory function?
– Waste products (protein metabolism)
– Drug elimination
– Glomerular Filtration
– Tubular Secretion
renal Endocrine function?
– Renin
– Erythropoetin
– Prostaglandins
– 1-alpha calcidol
renal Metabolism function?
– Vitamin D – Polypeptides • Insulin – Drugs • Morphine • paracetamol
What are the different types of drugs that act on renal tubules?
- Carbonic anhydrase inhibitors
- Osmotic Diuretics
- SGLT2 inhibitors
- Loop Diuretics
- Thiazides
- Potassium sparing diuretics
- Aldosterone antagonists
- ADH Antagonists
define Diuretic
increased production of urine
define Natriuretic
loss of sodium in urine
define Aquaretic
loss of water without electrolytes
What do carbonic anhydrase inhibitors do?
block sodium bicarbonate reabsorption in proximal tubules as inhibition of CA means less bicarbonate and H+ converted from CO2 in tubule cell ; acetazolamide
What are the effects of carbonic anhydrase inhibitor?
- loss of NaHCO3
- hypokalaemic
- metabolic acidosis (due to loss of bicarb)
Why does hypokalaemia occur with carbonic anhydrase inhibitors?
More sodium stays in the tubule and travels to the distal collecting duct where more is reabsorbed by ENAC channels (upregulation of ENAC) causing potassium to to be excreted through ROMK into the collecting duct as Na+K+ATPase needed to maintain Na conc gradient
What is carbonic anhydrase inhibitor used to treat?
Gluacoma and altitude sickness
- not really used as diuretics anymore
How long does it take to develop tolerance to carbonic anhydrase inhibitor, what does this mean?
Upregulation of channels downstream from the proximal tubule therefore making the actions of carbonic anhydrase inhibitor useless (??)
