Diuretics Flashcards
What is absorbed in the PCT?
Sodium and Bicarbonate
Absorption of bicarbonate in the PCT occurs how and through what enzyme?
carbonic anhydrase dissociates bicarbonate into CO2 and H2O
where else can we find carbonic anhydrase?
Choroid plexus
eye (ciliary ?)
what gets absorbed in the Thick limb of Henle? how much of this? by using what enzyme?
What is also absorbed as well?
what gets pumped out?
Na+ 20-30% by using Na+/2Cl-/K+ co-transporter
Mg and Ca2+
pumps out sodium, potassium and Chloride into the interstitium
what gets reabsorbed in the Distal Convoluted Tubule? when?
what gets secreted? how?
Ca2+ in presence of Parathyroid hormone
Na+ Cl- cotransporter
the cortical collecting duct is highly responsive to what hormone? what will it do?
this is the primary site of what process?
In the medullary collecting duct, what gets absorbed? in the presence of what hormone?
aldosterone, reabsorb Na+
acidification of urine and excretion of K+
water in presence of ADH
what drug is used in the PCT?
what drug is used in the Ascending Loop of Henle?
what drug is used in the DCT?
what drug is used in the collecting tube?
carbonic anhydrase inhibitor
Loop diuretics
Thiazides
2 types: spironolactone and amiloride/trimterene
what are the 2 carbonic anhydrase inhibitors?
acetazolamide
Dorzolamide
how does acetazolamide work?
what will we develop in terms of acidosis or alkalosis?
What will we lose as well as bicarbonate?
Carbonic Anhydrase inhibition in the ciliary epithelium leads to what? what is the clinical application for this?
carbonic anhydrase inhibition will act in the choroid plexus involving the CSF, what is the effect of this?
what is the clinical application for this?
- inhibits carbonic anhydrase in brush border and intracellularly so we will excrete bicarbonate in urine
- we will develop metabolic acidosis
- we will lose potassium
- it leads to reduced secretion of aqueous humor
- it can be used for glaucoma
- acidosis of the CSF will lead to hyperventilation
- can be used in high altitude sickness
what are the uses of carbonic anhydrase inhibitors?
- Glaucoma
- Urinary Alkalanization for acidic drug toxicity
- Acute of mountain sickness
- Significant metabolic alkalosis
what are the adverse reactions related with carbonic anhydrase inhibitors?
- Cross alergenicity with other sulfonamides
- Hyperchloremic metabolic acidosis
- Renal stones: Alkalinization of urine may cause Ca2+ precipitation
- Hypokalemia
what is an example of a loop diuretics?
what do loop diuretics do?
furosemide
inhibit Na+/K+/2Cl- cotransporter
what is the effect of using loop diuretics?
- produce massive sodium chloride diuresis
- it will reduce blood volume
- it will reduce edema rapidly
- will reduce the dilution of urine
- will reduce lumen positive potential (because you lose Ca2+ and Mg)
- will see loss of K+ and H+ ==> hypokalemic acidosis
what are the uses of loop diuretics?
- Treatment of edematous states including heart failure, ascites
- Acute Pulmonary edema or left ventricular failure
- mild to moderate heart failure
- severe hypercalemia
what are the adverse reactions of loop diuretics?
- Hypokalemia
- Ototoxicity
- cross hypersensitivity with sulfa drugs