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

Question 1

What is driving force for NaCl reabsorption in ThinAL

Answer 1

Osmotic Gradient

Question 1

Why is Cl reabsorbed in DCT/CD

Answer 1

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

Question 1

What drives Bicarb/Cl exchanger in DCT/CD

Answer 1

Increase in intracellular Bicarb

Question 2

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

Answer 2

Beta

Question 3

Under high acidosis conditions, DCT/CD cells express new

Answer 3

H transporter: H-K ATPase or Proton Pump

Question 5

Permeability of TDL to NaCl, Urea, Water

Answer 5

Minimal for NaCl and Urea, Highly permeable to water

Question 5

Active transport in Thin Ascending and Thin Descending Limbs

Answer 5

None

Question 5

Liddle’s Syndrome is characterized by

Answer 5

Increase Na reabsorption and K secretion

Question 6

How does Aldosterone increase Na reabsorption

Answer 6

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

Question 7

On which parts of nephron does Aldosterone act

Answer 7

DCT/CD

Question 8

How does Na reabsorption affect K secretion in DCT/CD

Answer 8

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

Question 9

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

Answer 9

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

Question 10

Where is the Na-Cl transporter present

Answer 10

Only in DCT

Question 10

What is Conn’s Syndrome

Answer 10

Aldosterone secreting tumore

Question 11

Amiloride and Triamterene block

Answer 11

Electrically conductive Na channels

Question 11

How does Aldosterone affect K

Answer 11

Increases secretion in DCT/CD

Question 11

What is Addison’s disease

Answer 11

Complete absence of Aldosterone

Question 12

How does plasma Ang 2 affect Aldosterone secretion

Answer 12

Low plasma AngII Decreases Aldosterone secretion

Question 13

Where is the electrically conductive Na channel present

Answer 13

In both DCT and CD

Question 13

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

Answer 13

Alpha

Question 14

Electrical acivity of electrically conductive Na channel

Answer 14

Makes lumen more negative; Membrane is depolarized

Question 16

ADH stimulates what in ThickAL

Answer 16

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

Question 17

Aldosterone increases what 3 channels

Answer 17

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

Question 18

What do Thiazide diuretics block

Answer 18

Na-Cl cotransporter

Question 19

NaCl reabsorption in ThinAL

Answer 19

Strong: 2/3 received volume

Question 20

What blocks Na-K-2Cl cotransporter

Answer 20

Loops

Question 21

Major luminal transporter in ThickAL

Answer 21

Na-K-2Cl

Question 22

Which cell type exchanges Na and K

Answer 22

Principal Cells

Question 24

Osmolarity change in ThinAL

Answer 24

Drops due to loss of NaCl

Question 24

Epithelial cells in ThickAL

Answer 24

Thick, many mitochondria

Question 25

Epithelial cells in ThinAL

Answer 25

Thin, few mitochondria

Question 26

How does plasma K affect Aldosterone secretion

Answer 26

Increased plasma K increases Aldosterone secretion

Question 28

\_\_\_ increases flow and Na output into distal tubule, therefore, \_\_\_

Answer 28

Loop diuretics, Increase K secretion

Question 29

Which cell type exchanges H+ and Bicarb

Answer 29

Alpha-Intercalated

Question 30

2 Regulatory factors of K secretion in DCT/CD

Answer 30

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

Question 32

Maximum of 1200 mOsm is due to what components

Answer 32

600 mOsm Urea, 600 mOsm NaCl

Question 33

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

Answer 33

Activation of two types of intercalated cells

Question 34

Where do Furosemide and Bumetanide act

Answer 34

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

Question 35

How do plasma ACTH levels affect Aldosterone secretion

Answer 35

Low plasma ACTH levels decrease Aldosterone secretion

Question 37

What stimulates Na-K-2Cl cotransporter

Answer 37

ADH

Question 39

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

Answer 39

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

Question 40

How is Bicarb reabsorbed in DCT/CD

Answer 40

Bicarb/Cl exchanger

Question 41

How is H+ secreted into lumen in DCT/CD

Answer 41

Active transport (against high gradient)

Question 43

\_\_\_ prevent membrane depolarization; no increase in \_\_\_

Answer 43

Amilorides, K secretion

Question 44

How does increased flow to DT/CD affect K secretion

Answer 44

Increases

Question 45

2 transport mechanisms for Na reabsorption in DCT/CD

Answer 45

Electrically conductive Na channels; Na-Cl cotransporter

Question 47

Net result of DCT/CD action if impermeable to water

Answer 47

Dilution of Urine

Question 48

3 Manifestations of Conn's Syndrome

Answer 48

Hypokalemia, Hypernatremia, HTN

Question 49

Under Alkalosis conditions, what channels switch directionality

Answer 49

H-ATPase and HCO3-Cl exchanger

Question 50

2 differences between H+ secretion in proximal vs distal

Answer 50

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

Question 51

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

Answer 51

Not entirely dependent on Aldosterone

Question 52

\_\_\_ block electro-neutral Na transport, without \_\_\_

Answer 52

Thiazides, affecting membrane depolarization

Question 53

What generates H+ in DCT/CD

Answer 53

Cellular Carbonic Anhydrase

Question 54

What blocks the Na-Cl cotransporter

Answer 54

Thiazide Diuretics

Question 55

What blocks the electrically conductive Na channels

Answer 55

Amiloride, Triamterene

Question 56

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

Answer 56

Na actively reabsorbed, K is secreted, Cl is reabsorbed

Question 57

Permeability of TAL to NaCl, Urea, Water

Answer 57

Extremebly water impermeable, Impermeable to Urea, Permeable to NaCl

Question 58

Driving force for Na-K-2Cl transporter

Answer 58

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