Xx - Renal Physiology Iv

Front 1

POTASSIUM

- most of the K+ cation is located in which fluid compartment?

Back 1

ICF

Front 2

POTASSIUM

- what K+ shift causes HYPERKalemia?

Back 2

K+ shift OUT (of cell)

Front 3

POTASSIUM

- what K+ shift causes HYPOKalemia?

Back 3

K+ shift IN (of cell)

Front 4

POTASSIUM

- is Filtered, Reabsorbed, or Secreted?

Back 4

all three

Front 5

POTASSIUM

- Causes of Hyperkalemia?

Back 5

(shift "O"ut = "O" (not I), & ABCDE)

- HyperOsmolarity
- Decreased Insulin

- Acidosis
- Beta adrenergic ANTAGONIST
- Cell lysis
- Digitalis
- Exercise

Front 6

POTASSIUM

- Causes of Hypokalemia?

Back 6

(shift "IN", so "IN" (not O) & high/for AB)

- Insulin
- HypoOsmolarity

- Alkalosis
- Beta-adrenergic AGONIST

Front 7

POTASSIUM

- Digitalis causes what K+ levels?

- Digitalis MOA?

Back 7

- Hyperkalemia

- Inhibits Na+/K+ pump
(blocked pump = no K+ uptake by cells)

Front 8

POTASSIUM

- how does Acidosis affect serum K+?

- MOA?

- occurs across which membrane?

Back 8

Hyperkalemia

Increases Exchange of extracellular Na+ (in to cell) for intracellular K+ (out of cell)

- Basolateral membrane

Front 9

POTASSIUM

- how does Hyperosmolarity affect serum K+?

- MOA?

Back 9

Hyperkalemia

HyperOSM = H2O diffusion OUT, thus K+ follows

Front 10

POTASSIUM

- what % of K+ is Reabsorbed @ the PT?

Back 10

67%

(with Na+ & H2O)

Front 11

POTASSIUM

- what % of K+ is Reabsorbed in TAL?

- occurs via what transporter?

Back 11

20%

NKCC Cotransport

Front 12

POTASSIUM

- K+ reabsorption or secretion @ DT & CD depends on what?

Back 12

Dietary K+ intake

Front 13

POTASSIUM

- @ DT & CD, what cells Reabsorb K+?

- involves what transporter?

- occurs ONLY when?

Back 13

- alpha-Intercalated cells (of DT & CD)

- H+/K+ ATPase

- LOW K+ Diet

Front 14

POTASSIUM

- @ DT & CD, what cells Secrete K+?

- how much K+ is secreted here?

Back 14

- Principle cells

- Variable levels of secretion
(depends on DA PAD)

Front 15

POTASSIUM

- what determines the level of K+ Secretion at the Principle cells?

Back 15

(DA PAD)

- Diet (of K+)
- Aldosterone levels

- pH
- Anions (of the lumen)
- Diuretics

Front 16

POTASSIUM

- Causes of Increased K+ Secretion @ Principal cells?

Back 16

(Increase K+ Secretion = Increase DA PAD)

- High K+ Diet
- High Aldosterone levels
- Thiazide & Loop Diuretics
- High luminal Anions (i.e. - Bicarb)
- High pH (Alkalosis)

Front 17

POTASSIUM

- Causes of Decreased K+ Secretion @ Principle cells?

Back 17

(Decrease K+ Secretion = Decreased DA PAD)

- Low K+ Diet
- Low Aldosterone levels
- K+ Sparing Diuretics
- Low luminal Anions
- Low pH (Acidosis)

Front 18

POTASSIUM

- K+ Secretion MOA @ Basolateral membrane of Principle cells?
(include Transporter)

- is this Active or Passive?

Back 18

- K+ is transported IN

via Na+/K+ pump

- ACTIVE

Front 19

POTASSIUM

- K+ Secretion MOA @ Luminal membrane of Principle cells?
(include Transporter)

- is this Active or Passive?

Back 19

- K+ is secreted into lumen

via K+ channels

- PASSIVE

Front 20

POTASSIUM

- Passive secretion of K+ occurs in which cells?

- via what transporter?

- of which membrane?

- is Determined by?

Back 20

- Principle cells (of DT & CD)

- K+ channels

- Luminal membrane

- Electrical-Chemical Gradient
(of K+ across luminal membrane)

Front 21

POTASSIUM

- HIGH K+ diet affects Intracellular [K+] how?

- thus causing what effect on the driving force for K+ secretion?

Back 21

- Increases

- Increases

Front 22

POTASSIUM

- LOW K+ diet affects Intracellular [K+] how?

- thus causing what effect on the driving force for K+ secretion?

Back 22

- Decreases

- Decreases

Front 23

POTASSIUM

- what type of K+ diet can have an effect on K+ Reabsorption?

- MOA?

- occurs in which cells?

Back 23

- LOW K+ diet
(Increases K+ reabsorption)

- Stimulates H+/K+ ATPase

- Alpha-Intercalated cells (of DT & CD)

Front 24

POTASSIUM

- what can increase the number of K+ channels on the Luminal membrane @ DT & CD?

Back 24

- Aldosterone

Front 25

POTASSIUM

- Hyperaldosteronism effects on K+ secretion?

- thus causing what K+ serum levels?

Back 25

- Increases K+ secretion

- HYPOKalemia

Front 26

POTASSIUM

- Hypoaldosteronism effects on K+ secretion?

- thus causing what K+ serum levels?

Back 26

- Decreases K+ secretion

- HYPERKalemia

Front 27

POTASSIUM

- Acidosis effects on K+ secretion?

Back 27

(Decrease pH = Decrease K+ secretion)

- Decreases K+ secretion

Front 28

POTASSIUM

- Alkalosis effects on K+ secretion?

Back 28

(Increase pH = Increase K+ secretion)

- Increases K+ secretion

Front 29

POTASSIUM

- which diuretics increase K+ secretion?

- MOA?

Back 29

- Thiazides
- Loops (FBE)

- Dilutes the distal [K+], thus increasing the EC drive for K+ secretion

Front 30

POTASSIUM

- which diuretics decrease K+ secretion?

Back 30

- K+ sparing diuretics (SAT)

- Spironolactone acts as Aldosterone ANTAGONIST
- Amilioride & Triamterene directly acts on Principle cells.

Front 31

POTASSIUM

- Excess Luminal Anions (i.e. Bicarb) affects K+ secretion how?

- MOA?

Back 31

- Increases K+ secretion

- excess Anions increase Negativity of Lumen, thus increasing EC drive
(thus favoring K+ secretion)

Front 32

UREA

- Urea can be reabsorbed where?

Back 32

- PT
- Inner Medullary CD

(impermeable everywhere else)

Front 33

UREA

- 50% of filtered urea is reabsorbed where?

- via what transporter?

Back 33

- PT

- no transporter. Occurs Passively

Front 34

UREA

- ADH affects Urea reabsorption?

- MOA?

- ADH effects on Urea occurs WHERE?

Back 34

- Increases Reabsorption

- by increasing Urea permeability

- Inner Medullary CD

Front 35

UREA

- Urea Recycling occurs where?

- Urea Reabsorption WHERE will contribute to Urea Recycling?

Back 35

- Inner Medulla

- @ Inner Medullary CD

Front 36

UREA

- Urea Excretion varies with ______

Back 36

- Urine Flow Rate

(inverse of Water reabsorption)

Front 37

UREA

LOWER H2O Reabsorption (i.e. w/ Diuretics) means what for:

- Urine Flow Rate?
- Urea Reabsorption?
- Urea Excretion?

Back 37

- Higher urine flow rate

- Lower urea reabsorption

- Higher urea excretion

Front 38

PHOSPHATE

- what % of Phosphate is reabsorbed?

- what % of Phosphate is excreted?

Back 38

85%

15%

Front 39

PHOSPHATE

- Phosphate is reabsorbed where?

- what Transporter(s) used?

Back 39

PT

Na+/Phosphate Cotransporter

Front 40

PHOSPHATE

- Phosphate is excreted in what form?

- this form is called what?

- why?

Back 40

H2PO4-

Titratable Acid

b/c it acts as a Urinary Buffer for H+

Front 41

PHOSPHATE

- PTH has what effect on Phosphate?

- MOA?

Back 41

- inhibits reabsorption of phosphate

- inhibits the Na+/Phosphate Cotransporter of PT

Front 42

PHOSPHATE

- PTH causes what changes to [Phosphate] in the URINE?

- what other concentration in URINE is affected and how?

- what is the MOA of above?

Back 42

- Increases Phosphate in urine

- Increases cAMP in urine

- PTH activates Adenylate Cyclase
(which generates cAMP)

Front 43

CALCIUM

- how much of PLASMA Calcium is FILTERED?

Back 43

60%

Front 44

CALCIUM

- Passive Ca2+ Reabsorption occurs where?

- How much of Ca2+ is reabsorbed here?

Back 44

- PT & TAL

- 90%

Front 45

CALCIUM

- Active Ca2+ Reabsorption occurs where?

- How much of Ca2+ is reabsorbed here?

Back 45

- DT & CD

- 8%

Front 46

CALCIUM

- Calcium reabsorption is COUPLED to reabsorption of what other CATION?

- where does this reabsorption take place?

- is this reabsorption Active or Passive?

Back 46

- Na+

- TAL

- Passive
(PT & TAL are passive locales)

Front 47

CALCIUM

- Which diuretics can be used for Hypercalcemia?

- Which one from above is used for IDIOPATHIC Hypercalciuria?

Back 47

- Loops

- Thiazide

Front 48

CALCIUM

- which diuretic has an indirect effect on Calcium reabsorption?

- occurs where

- describe MOA of this Indirect process

Back 48

- Loops

- PT

- Loops diuretics inhibit Na+ reabsorption, which is coupled to Calcium reabsorption, thus Calcium reabsorption inhibited

Front 49

CALCIUM

- PTH affects calcium how?

- PTH effects occur where?

- PTH effects MOA?

Back 49

- Increases Ca2+ Reabsorption

- TAL

- PTH activates Adenylate Cyclase
(thus Increasing Ca2+ reabsorption)

Front 50

CALCIUM

- Which diuretic affects calcium reabsorption at the DT?

- what is the effect?

Back 50

- Thiazides

- Increases Ca2+ reabsorption
(thus decreasing its excretion)

Front 51

CALCIUM

- Calcium COMPETES with what Cation for Reabsorption?

- where does this occur?

Back 51

- Magnesium

- TAL

Front 52

MAGNESIUM

- Mg2+ is reabsorbed where?

Back 52

- PT
- TAL
- DT

Front 53

MAGNESIUM

- Mg2+ competes for reabsorption with what other cation?

- this occurs where?

Back 53

- Calcium
(both are 2+ cations)

- TAL

Front 54

MAGNESIUM

- HYPERMagnesemia has what effect on Calcium?

Back 54

- Inhibits Calcium Reabsorption

(thus Increases Ca2+ Excretion)

Front 55

MAGNESIUM

- HYPERCalcemia has what effect on Magnesium?

Back 55

- Inhibits Mg2+ Reabsorption

(thus Increases Mg2+ Excretion)

Front 56

PTH

- increases reabsorption of what ion?
- @ where?

- decreases reabsorption of what ion?
- @ where?

Back 56

- Calcium reabsorption
- DT

- Phosphate reabsorption
- PT

Front 57

Calcium Reabsorption :

- Coupled with what Cation? where?

- Competes with what Cation? where?

Back 57

- Na+
(@ TAL)

- Mg2+
(@ TAL)