05.07 - Loop, DT, CD (Rao) - PP, LG, No reading, Not watched Flashcards Preview

Renal > 05.07 - Loop, DT, CD (Rao) - PP, LG, No reading, Not watched > Flashcards

Flashcards in 05.07 - Loop, DT, CD (Rao) - PP, LG, No reading, Not watched Deck (58):
1

What is driving force for NaCl reabsorption in ThinAL

Osmotic Gradient

1

Why is Cl reabsorbed in DCT/CD

Na reabsorption is greater than K secretion, therefore Cl is reabsorbed

1

What drives Bicarb/Cl exchanger in DCT/CD

Increase in intracellular Bicarb

2

Which has bicarb channel in luminal membrane: alpha or beta intercalate

Beta

3

Under high acidosis conditions, DCT/CD cells express new

H transporter: H-K ATPase or Proton Pump

5

Permeability of TDL to NaCl, Urea, Water

Minimal for NaCl and Urea, Highly permeable to water

5

Active transport in Thin Ascending and Thin Descending Limbs

None

5

Liddle's Syndrome is characterized by

Increase Na reabsorption and K secretion

6

How does Aldosterone increase Na reabsorption

(1) Increases number of luminal Na channels; (2) Increases basolateral Na/K; (3) Increases ATP synthesis

7

On which parts of nephron does Aldosterone act

DCT/CD

8

How does Na reabsorption affect K secretion in DCT/CD

Decrease Na reabsorption results in higher lumen-negative transepithelial voltage = K secretion

9

% of filtered load received by DCT/CD of Water, NaCl, KCl, and Urea

10%, less than 10, less than 10, 50

10

Where is the Na-Cl transporter present

Only in DCT

10

What is Conn's Syndrome

Aldosterone secreting tumore

11

Amiloride and Triamterene block

Electrically conductive Na channels

11

How does Aldosterone affect K

Increases secretion in DCT/CD

11

What is Addison's disease

Complete absence of Aldosterone

12

How does plasma Ang 2 affect Aldosterone secretion

Low plasma AngII Decreases Aldosterone secretion

13

Where is the electrically conductive Na channel present

In both DCT and CD

13

Which has proton channel in luminal membrane: alpha or beta intercalated

Alpha

14

Electrical acivity of electrically conductive Na channel

Makes lumen more negative; Membrane is depolarized

16

ADH stimulates what in ThickAL

Na-K-2Cl cotransporter (and thus reabsorption of Na)

17

Aldosterone increases what 3 channels

(1) Na/K ATPase; (2) Luminal K; (3) Lumina Na

18

What do Thiazide diuretics block

Na-Cl cotransporter

19

NaCl reabsorption in ThinAL

Strong: 2/3 received volume

20

What blocks Na-K-2Cl cotransporter

Loops

21

Major luminal transporter in ThickAL

Na-K-2Cl

22

Which cell type exchanges Na and K

Principal Cells

24

Osmolarity change in ThinAL

Drops due to loss of NaCl

24

Epithelial cells in ThickAL

Thick, many mitochondria

25

Epithelial cells in ThinAL

Thin, few mitochondria

26

How does plasma K affect Aldosterone secretion

Increased plasma K increases Aldosterone secretion

28

___ increases flow and Na output into distal tubule, therefore, ___

Loop diuretics, Increase K secretion

29

Which cell type exchanges H+ and Bicarb

Alpha-Intercalated

30

2 Regulatory factors of K secretion in DCT/CD

Increased flow by diuretics inc. K secretion; Decreased Na reabsorption (diuretics) results in higher lumen-negative transepithelial charge

32

Maximum of 1200 mOsm is due to what components

600 mOsm Urea, 600 mOsm NaCl

33

How is switch of H-ATPase and HCO3-Cl exchanger achieved

Activation of two types of intercalated cells

34

Where do Furosemide and Bumetanide act

Cl site in N-K-2Cl cotranspoter in ThickAL

35

How do plasma ACTH levels affect Aldosterone secretion

Low plasma ACTH levels decrease Aldosterone secretion

37

What stimulates Na-K-2Cl cotransporter

ADH

39

3 other channels in ThickAL besides Na-K-2Cl and Na-K

Basolateral Cl channel (reabsorb); Basolateral K-Cl cotransporter (reabsorb); Apical K (secrete)

40

How is Bicarb reabsorbed in DCT/CD

Bicarb/Cl exchanger

41

How is H+ secreted into lumen in DCT/CD

Active transport (against high gradient)

43

___ prevent membrane depolarization; no increase in ___

Amilorides, K secretion

44

How does increased flow to DT/CD affect K secretion

Increases

45

2 transport mechanisms for Na reabsorption in DCT/CD

Electrically conductive Na channels; Na-Cl cotransporter

47

Net result of DCT/CD action if impermeable to water

Dilution of Urine

48

3 Manifestations of Conn's Syndrome

Hypokalemia, Hypernatremia, HTN

49

Under Alkalosis conditions, what channels switch directionality

H-ATPase and HCO3-Cl exchanger

50

2 differences between H+ secretion in proximal vs distal

In distal, H+ is secreted against high gradient actively; Also, distal epithelium is impermeant to diffusion

51

What does Addison's disease tell us about Na reabsorption and K secretion

Not entirely dependent on Aldosterone

52

___ block electro-neutral Na transport, without ___

Thiazides, affecting membrane depolarization

53

What generates H+ in DCT/CD

Cellular Carbonic Anhydrase

54

What blocks the Na-Cl cotransporter

Thiazide Diuretics

55

What blocks the electrically conductive Na channels

Amiloride, Triamterene

56

Reabsorption/Secretion of Na, K, Cl in DCT/CD

Na actively reabsorbed, K is secreted, Cl is reabsorbed

57

Permeability of TAL to NaCl, Urea, Water

Extremebly water impermeable, Impermeable to Urea, Permeable to NaCl

58

Driving force for Na-K-2Cl transporter

Na electrochemical gradient (set up by Na-K ATPase)