DIURETICS MABP MABP MABP Sensed" ECFV Nat excretion rate Sensed ECFV 2 Net△Na+ dietary Na+ intake 6 Na+→ Nat excretion osses Total intake other losses t(e.g,swea feces, etc. ECFV 3 Na thirst H20 intake restriction Net△Na+ △EcFV mechanisi H2O excretion Interrelationships among renal function, Nat intake, water homeostasis, distri. bution of extracellular uid volume(ECFV), and mean arterial blood pressure(MABP)
A. Diuretic drugs .a diuretic is any substance influence the rates of transport of Nat, K+ Cl, HCO3 and urate, increases urine and solute excretion
A. Diuretic drugs •A diuretic is any substance influence the rates of transport of Na+, K+, Cl-，HCO3 - and urate, increases urine and solute excretion
A. Diuretic drugs Classification of diuretic drugs Loop diuretics thick ascending limb of Henle loop high efficacy inhibiting Na+-K+-2CI- symport furosemide呋塞米 Thiazide diuretics distal convoluted tubule moderate efficacy inhibiting Nat-CI- symport hydrochlorothiazide氢氯噻嗪 K+-sparing diuretics late distal tubule and collecting loW efficacy duct spironolactone螺内酯 inhibiting renal epithelial na channels
Classification of diuretic drugs Loop diureticshigh efficacy furosemide 呋塞米 thick ascending limb of Henle loop inhibiting Na+-K+-2Cl- symport Thiazide diuretics moderate efficacy hydrochlorothiazide 氢氯噻嗪 distal convoluted tubule inhibiting Na+-Cl- symport K+-sparing diuretics low efficacy spironolactone 螺内酯 late distal tubule and collecting duct inhibiting renal epithelial Na+ channels A. Diuretic drugs
ACETAZOLAMIDE THIAZIDES o Carbonic anhydrase inhibitor which Inhibits the reabsorption of HcO3 Inhibit reabsorption of Na* and cr in distal tubule in the promixal convoluted tubule resulting in retention of water. Weak diuretic propertles Most commonly used diuretics. filtrate Proximal Distal convoluted SPIRONOLACTONE convoluted AMILORIDE tubule tubule TRIAMTERENE ● Spironolactone, an aldosterone antagonist, inhibits the aldosterone. mediated reabsorption of Na’ and secretion of K ●Am∥ oride and triamterene Ascending 3 lod block Na* channels p o Hen e These agents can prevent loss of K+ that occurs with thiazide or loop diuretic BUMETANIDE, FUROSEMIDE Descending 2 loc op of TORSEMIDE, ETHACRYNIC ACID Henle ● Inhibit the na/ K*/CI"co transport in ascending loop of Collecting Henle, resulting in retention of duct Na*, cr and water in the tubule e These drugs are the most efficacious of the diuretics
A. Diuretic drugs Loop diuretics NH-CH O Furosemide 呋塞米 H2NO2S COOH NH-CH2-CH2-CH2-CH3 Bumetanide HoNOS 布美他尼 Etacrynic acid H3C-H2C-C-C O-CHo-C-OH 依他尼酸 CH
Furosemide 呋塞米 Bumetanide 布美他尼 Etacrynic acid 依他尼酸 A. Diuretic drugs Loop diuretics