Flashcards in Pharmacology 3 Deck (34)
Where do osmotic diuretics work?
Name an osmotic diuretic
Where does most isoreabsorption of water take place?
Do carbonic anhydrase inhibitors cause an alkalois or acidosis?
They cause excretion of HCO3 with Na+, K+ and H20
-cause an ALKALINE diuresis and METABOLIC acidosis will result
Used for prophylaxis of altitude sickness
Carbonic anhydrase inhibitors
Inhibits secretion of vasopressin
Enhances secretion of vasopressin
Lithium and vasopressin
Blocks effect of vasopressin
What do V1a receptors mediate?
What do V2 receptors mediate?
H2O resorption in collecting tubule
What happens if you block V2 receptors?
Causes excretion of water without accompanying Na+
(this then raises plasma Na+ concentration)
Competitive antagonists of vasopressin receptors
When is tolvaptan used?
Drug used in SIADH
Where does reabsorption of glucose take place?
Where is SGLT1 expressed?
Intestine and the kidney
Where is SGLT2 expressed?
Almost exclusively in the proxiaml tubule
SGLT2 absorb up to ____ glucose
SGLT1 absorb up to ____ glucose
How is glucose reabsored?
Secondary active transport (apical membrane)
Facilitated diffusion (basolateral membrane)
2 sodium for 1 glucose
1 sodium for 1 glucose
Canagliflozin, dapagliflozin, empagliflozin
Inhibitor of SGLT2
What do SGLT2 inhibitors cause?
Excretion of glucose
Decrease in HbA1c
How are prostaglandins formed?
Formed from fatty acid arachidonic acid by COX1 and 2
Where is PGE2 made?
Where is PGI2 made?
When are prostaglandins synthesised?
In response to ischaemia, mechanical trauma, angiotensin II, ADH and bradykinin
How do prostaglandins affect GFR?
-a direct vasodilator effect upon the afferent arteriole
-release renin = lead to increased levels of angiotensin II that vasoconstricts efferent arteriole
Detrimental "triple whammy" effect
ACEI, diuretic and NSAID
Why do NSAIDs precipitate renal failure?
Non-steroidal anti-inflammatory drugs (NSAIDS) inhibit COX and may precipitate acute renal failure (greatly decreased GFR) in conditions where renal blood flow is dependent upon vasodilator prostaglandins (cirrhosis of the liver, heart failure, the nephrotic syndrome)
What are probenecid and sulfinpyrazole?
Block reabsorption of urate in proximal tubule