DIT Renal 2. Nephron and Diuretics Flashcards Preview

Pathology > DIT Renal 2. Nephron and Diuretics > Flashcards

Flashcards in DIT Renal 2. Nephron and Diuretics Deck (45):
1

What class of drugs inhibit the Na+/2Cl-/K+ symporter in the thick ascending limb?

Loop diuretics

2

What determines how much water is reabsorbed in the distal tubules and the collecting ducts?

ADH

3

What two types of cells compose the collecting duct and the last segment of the distal tubule? What do they do?

Principal cells:
1. reabsorb H2O and Na+
2. secrete K+

Intercalated cells:
1. secrete H+ or HCO3-
2. reabsorb K+

4

What are the two types of intercalated cells?

alpha cells - H+ secreting cells


beta cells - HCO3- secreting cells

6

What affect does aldosterone have on the intercalated cells and principal cells of the collecting duct?

Intercalated cells - stimulates acid secretion

Principal cells - increase Na+ reabsorption and K+ secretion

7

What drug antagonizes aldosterone's action on the principal cells of the collecting duct, thereby promoting Na+ excretion and inhibiting K+ excretion?

Spironolactone
Eplerenone

8

What are the critical steps involved in excreting dilute urine?

1. Dilution of fluid in the TAL as solute is reabsorbed and water remains in lumen (d/t impermeability of H2O in TAL)

2. Absence of ADH --> distal tubule and cortical collecting duct impermeable to H2O

3. Tubular fluid is diluted even more as solute is removed from tubular fluid in distal tubule and cortical collecting duct but water remains

4. B/C of low fluid osmolality in collecting duct and slight permeability of medullary collecting duct to urea, urea enters the tubule from the medullary interstitium thereby keeping the osmolality of the medial interstitium low

13

What class of diuretics directly affects principal cells?

K+ sparing diuretics

28

reabsorbs 67% of the fluid and electrolytes filtered by the glomerulus

proximal tubule

31

segment responsible for concentrating urine

collecting duct

34

glaucoma

mannitol
acetazolamide

35

site of secretion of organic anions and cations

proximal tubule

38

always impermeable to water

thick ascending limb

41

permeable to water only in the presence of ADH

late distal tubule and collecting ducts

44

site of the Na+/2Cl-/K+ co transporter

thick ascending limb

47

site of isotonic fluid reabsorption

proximal tubule

50

site responsible for diluting urine

thick ascending limb

53

only site where glucose and amino acids are reabsorbed

proximal tubule

56

water reabsorption in the loop of henle

thin descending limb

59

Triamterene

K+ sparing

62

Acetazolamide

carbonic anhydrase inhibitor

65

Hydrochlorothiazide

thiazide diuretic

68

Bumetanide

loop

71

Spironolactone

K+ sparing diuretic (aldosterone antagonist)

74

Chlorothiazide

thiazide

77

Ethacrynic acid

loop (not a sulfa drug)

80

Mannitol

osmotic diuretic

83

Metolazone

thiazide diuretic

86

Chlorthalidone

thiazide diuretic

89

Furosemide

loop diuretic

92

Amiloride

K+ sparing diuretic

95

Torsemide

loop diuretic

98

acute pulmonary edema

loops

101

idiopathic hypercalciuria (-->calcium stones)

thiazide diuretics

107

mild to moderate CHF with expanded ECV

loops (maybe thiazide if mild)

110

in conjunction with loops or thiazides to retain K+

K+ sparing diuretics

113

edema associated with nephrotic syndrome

loop diuretic

116

increased intracranial pressure

mannitol

119

mild to moderate HTN

thiazides

122

hypercalcemia

loops

125

altitude sickness

acetazolamide

128

hyperaldosteronism

Spironolactone

129

What is the site of action of mannitol?

proximal convoluted tubule

130

What is the site of action of the thiazides?

distal convoluted tubule

131

A pt with heart failure exacerbation needs medical diuresis but has a sulfa allergy. What diuretic can be used?

Ethacrynic acid