Na,K, Cl

Question 1

How can water be lost from the body?

Answer 1

insensible loss, sweat, feces, urine = 2.5L/day
Other: infections, malabsorption

Question 2

How would the kidneys respond to large amounts of water?

Answer 2

this would cause a decrease in solutes and osmotic gradients - water will flow into cells where osmotic conc is higher - kidney will quicky excrete water to compensate - increased urine volume

Question 3

How would the kidneys respond to large quantity of salt

Answer 3

increase plasma osmotic gradient - cells shrink - kidneys excrete more solutes

Question 4

What is normal osmotic movement in and out of the kidneys

Answer 4

300 mOsm

Question 5

Different b/w descending and ascending limp of kidneys

Answer 5

D: permeable to water
A: permeable to ions, and solute, water, has Na:K pumps

Question 6

Proximal tubule

Answer 6

Filters 100%. reabsorbs up to 65%, permeable to water, salts, bicarbonate, glucose, AA, creatinine, urea

Question 7

ADH / Vasopression

Answer 7

hormone for renal control of water reabsorption via AQP2
- Distal tubule and collecting ducts

Question 8

Aldosterone

Answer 8

Reabsorption of Na+ via Na/K exchange.
RAA for vasoconstriction = increased BP
- K excreted, Na+ retained + water
-distal tubule and collecting ducts

Question 9

ADH action through the cell

Answer 9

Binds receptor
AQP2 apical transcription apical `
Accept water
Leave Via AQP3 basolateral

Question 10

Aldosterone action through the cell

Answer 10

Increases luminal Na+ channels & Na/K pumps basolateral
influx of sodium into the cell and increase in pump then increase sodium into plasma - water follows, stimulates thirst

Question 11

Difference between a salt deficit and a excess water loss

Answer 11

Salt deficit will increase Sympathetic activity, decrease GFR, increase aldosterone and ADH
Water loss will increase plasma osmolarity, stimulate ADH & thirst

Question 12

ANP - Atrial Antidiuretic hormone

Answer 12

response to increased BP, acts on efferent and afferent arteriole, and DCT,
- Vasodilation + inhibits Na uptake

Question 13

ANG II

Answer 13

Response to hypotension on afferent and efferent arterioles.
Vasoconstriction + Na absorption

Question 14

Describe kidney functions and what occurs with CKD in regards to those functions

Answer 14

Sodium balance —> Na retention and volume overload
K+ excretion —> Hyperkalemia
Acid excretion —> Metabolic acidosis - decrease H+ availability
Ca/P balance —> Increase phosphate and decrease calcium
Erythropoiesis —> Anemia

Question 15

What would cause excessive Na and Cl retention??

Answer 15

Sea water and fast infusion of saline
Hypersecretion of Aldosterone (Crushers syndrome = decrease K, increase PH + BP)
Congestive heart failure (body thinks it needs salt to increase heart rate)
Hypernatremia ([Na+] > 145mmol/L) due to decrease in TB water relative to Na+
Failure of kidney control

Question 16

What would cause a deficiency in Na and Cl-

Answer 16

Water > Solute
hypernatremia (hypervolemia, hypovolemia, euvolemia)
too much water during sports
non-renal loses + renal loses (ex. vomit, diarrhea – diuretics, diabetes)

Question 17

Fluid volume sodium symptoms association effects?

Answer 17

BP and CNS function

Question 18

difference + Similarity b/w hypo/hyper kalemia

Answer 18

hypo - < 3.5mmol, increased K+ excretion, hyperpolarize, inadequate intake, extra to intracellular shift
Hyper - >5.5 mmol, combo of excessive increase intake and decreased excretion, hypopolarize , intra to extracellular shift
both: affect muscle contractions or cardiac function

Question 19

All potassium symptoms associated with

Answer 19

nerve transmission and muscle contraction

Question 20

AI and UL for salt

Answer 20

3.8g/day AI
6g /day UL
(Note salt is 40% sodium)

Question 21

What is the na intake associated with High BP

Answer 21

2.3g/day

Question 22

What is the min Daily intake recommended for salt

Answer 22

500mg na, 750mg cl

Question 23

why does the food industry industry rely on salt

Answer 23

Color developer , Fermentation, Binder, Texture aid, Preservative

Question 24

What is the potassium AI and recommended intake

Answer 24

4.7g/day AI
2g/d recommended

Question 25

Food sources of potassium

Answer 25

plum, banana, plantains, melon, raisins, OJ, milk, plain yogurt

Question 26

Describe the range of values of Na, K, & Cl inside and outside of cells

Answer 26

Na - outside: 135-148 mmol/L. Inside: 12 mmol/L
Cl - outside: 98-108 mmol/L. Inside: 2 mmol/L
K - outside: 3.8-5.5 mmol/L. Inside: 150 mmol/L

Question 27

What controls electrolyte disturbances and balance in the body

Answer 27

Movement of ions: passive and active
Selective permeability: prevents movement of proteins and phosphates

Question 28

describe fluid distribution and body compartments

Answer 28

Extracellular fluid: all fluid outside cell, including fluid in blood and plasma. Also contains interstitial fluid between cells and outside BV
35% - 25% is interstitial fluid
Intracellular fluid - all fluid inside cells - 65%

Question 29

Electrical gradient

Answer 29

overall charge / overall neg charge - adding ions
outflow of more Na+ than inflow of K+
(3 Na+, 2K+ in)

Question 30

Chemical gradient

Answer 30

simply the molecule:
extracellular Na vs cytoplasm

Question 31

Main fxn of Na/K

Answer 31

Maintains ionic homeostatsis, regulates cell volume, basis for water soluble absorption

Question 32

What is the purpose active absorption of Na+

Answer 32

primary mechanism for passively absorbing draws Cl- ions, monosaccarides, AA, water

Question 33

What is the importance of the asymmetric distribution of channels/pumps

Answer 33

these pumps promote Na+ to pumped out and K IN
generates a gradient from luminal side intracellularly - allows transport of molecules in free of charge

Question 34

What allows Na+ to be 95% - 100% absorbed

Answer 34

Gradient created by Na, K-ATPase pump
Na+/glucose co-transport, Na/H exchange, Na/Cl co-transport

Question 35

What allows K+ to be 85-90% absorbed

Answer 35

via colon by passive diffusion or H+/K+ pump
Aldosterone can cause a shift

Question 36

What organs play the biggest role in electrolyte balance

Answer 36

Kidneys
Intestine (mnor)

Question 37

which will cause faster depolarization hyperkalemia or hypokalemia

Answer 37

hyperkalemia causes faster depolarization: muscle spasm
Hypokalemia causes hyperpolarization (really low membrane reset) because of a bigger electrochemical difference: decrease muscle contraction