Diuretics and Natriuretics • • Most are filtered in the glomerulus and act on luminal epithelium Bind to and usually block luminal channels SGLT-2 Inhibitors • • • • Used for diabetic patients Inhibits Na-Glucose cotransporter in PCT This results in Na and glucose loss in urine Reduces blood glucose, weight, ↓risk of MI/stroke, protects kidneys, etc. Loop Diuretics • • • • • • Na+/K+/2Cl- cotransporter inhibitor E.g. frusemide Increases urinary loss of Na, K, Mg, Ca Interferes with urinary concentration, not dilution ↑Urinary volume Useful for treating fluid retention Diluting Segment Inhibitors/Thiazides • Block Na+/Cl+ cotransporter  Limits body ability to dilute urine Rule to remember: • • Loop diuretics secrete Na in dilute urine Thiazides excrete sodium in concentrated urine (because ADH has final say in water concentration) Aldosterone Antagonists • • • E.g. spironolactone, epleronone Inhibit aldosterone  ↓Na reabsorption Secondarily: ↓K excretion and ↓H+ excretion Epithelial Na Channel Blockers • • • • E.g. amiloride ↓Na reabsorption ↓K secretion (K sparing) ↓H+ secretion  acid accumulation