Renal 6 - sodium

Question 1

what kind of hormone is ADH

Answer 1

peptide

Question 2

what is the role of osmoreceptors

Answer 2

sense increase in plasma osmolarity

Question 3

where are osmoreceptors

Answer 3

in the hypothalamus

Question 4

where is ADH made

Answer 4

cell of the supra-optic nucleus in the hypothalamus

Question 5

where is ADH secreted

Answer 5

posterior pituitary

Question 6

where is the site of ADH action

Answer 6

collecting duct cells

work on specific aquaporins

Question 7

what is the mechanism of action of ADH

Answer 7

alters water permeability of the luminal membrane of cortical collecting ducts (increases reabsorption)

Question 8

what are aquaporins

Answer 8

water channels found in renal tubule cells (and other cells)

Question 9

which aquaporins in the proximal convoluted tubules

Answer 9

AQP1

Question 10

which aquaporins in the collecting ducts

Answer 10

AQP 2 3 4

Question 11

what aquaporin does ADH regulate and how and where

Answer 11

AQP2
increase gene transcription
luminal side of collecting duct
(physiological regulation)

Question 12

are AQPs on the basolateral membranes regulated by ADH

Answer 12

no

Question 13

what happens to AQP2 when there is no vasopressin

Answer 13

the channels are reabsorbed into vesicles

less water reabsorption

Question 14

what happens to permeability of water without ADH to the cortical collecting ducts

Answer 14

nearly impermeable to water

Question 15

what is water diuresis

Answer 15

lots of fluid loss through urine

Question 16

what causes water diuresis

Answer 16

absence of ADD

Question 17

what can cause an increase in ADH (environment)

Answer 17

warm, shock, pain, no water

Question 18

what can cause an decrease in ADH (environment)

Answer 18

cold, humid, alcohol

Question 19

what does high ADH cause

Answer 19

retain water

Question 20

what does low ADH cause

Answer 20

lose water

Question 21

what is central diabetes insipidus

Answer 21

failure to release ADH from posterior pituitary

Question 22

what is nephrogenic diabetes insipidus

Answer 22

defect at level of nephron tubule cells,

weak collecting duct cells

Question 23

does diabetes insipidus involve sugar?

Answer 23

nah fam, has to do with ADH or ADH RECEPTORS

Question 24

where does most of the gradient come from

Answer 24

50% from NaCl

Question 25

how does the interstitial space change in dry environments

Answer 25

more of a gradient

Question 26

how does the interstitial space change in non dry environments

Answer 26

less of a gradient

Question 27

what is water diuresis

Answer 27

when excess water is excreted without excess solute in urine

Question 28

what condition is associated with water diuresis

Answer 28

diabetes insipidus

Question 29

what causes diabetes insupidus

Answer 29

messed up vasopressin/ADH

Question 30

what is osmotic diuresis

Answer 30

excess solute in urine that is associated with high levels of water excretion

Question 31

what condition is associated with omsotic diuresis

Answer 31

diabetes mellitus

Question 32

what are short term handlings of low Na in plasma

Answer 32

baroreceptors regulate CFR, they become desensitized

Question 33

what are long term handlings of low Na in plasma

Answer 33

aldosterone promotes Na reabsorption

Question 34

what does atrial natriuretic peptide do

Answer 34

regulates GFR and inhibits Na+ reabsorption | inhibits aldosterone actions

Question 35

how does the body adapt to high Na in plasma

Answer 35

releases atrial natriuretic peptide (regulate GFR, inhibit Na reabsorption, inhibit aldosterone).

Question 36

what are baroreceptors

Answer 36

nerve endings that are sensitive to stretch, change in blood volume & peripheral resistance

Question 37

where are baroreceptors located

Answer 37

carotic sinus, aortic arch, major veind, intrarenal (JG cells of JGA)****

Question 38

do baroreceptors directly or indirectly detect sodium

Answer 38

indirectly by sensing water volume

Question 39

what do baroreceptors dectect

Answer 39

change in blood volume, BP and stretch

Question 40

what does activation of baroreceptors cause (5 things)

Answer 40

increased nerve impulse frequency and activation of the ANS | increate afferent arteriolar constriction, decrease GFR, increase Na reabsorption

Question 41

what kind of hormone is aldosterone

Answer 41

steroid

Question 42

where is aldosterone secreted from

Answer 42

adrenal cortex

Question 43

what triggers the synthesis and release of aldosterone

Answer 43

low sodium

Question 44

is the effect of aldosterone short or long term

Answer 44

long term

Question 45

where is the site of action of aldosterone

Answer 45

late distal and cortical collecting duct

Question 46

what are the 3 actions of aldosterone

Answer 46

induces synthesis of Na transport proteins | stimulates Na reabsorption reduces Na excretion

Question 47

what is Na+ reabsorption linked to

Answer 47

K secretion

Question 48

what regulates aldosterone secretion

Answer 48

low total body [Na+]

Question 49

what does angiotension 2 do and where

Answer 49

acts on adrenal cortex to control secretion of aldosterone

Question 50

where is renin secreted from

Answer 50

the juxtaglomerular cells of the JGA in the kidney

Question 51

what do the baroreceptors of the JGA sense

Answer 51

low NaCl

Question 52

what secretes angiotensinogen

Answer 52

the liver

Question 53

what does ACE do

Answer 53

angiotension 1 to 2

Question 54

what does angiotension 2 do

Answer 54

cause vasoconstriction and raises blood pressure

Question 55

where does angiotension 2 cause

Answer 55

aldosterone release from the adrenal cortex

Question 56

what secretes renin

Answer 56

juxtaglomerular cells on the wall of afferent arterioles

Question 57

what kind of cells are juxtaglomerular/ what do they sense

Answer 57

mechanoreceptors that sense circulating plasma volume

Question 58

where are macula densa

Answer 58

wall of distal convoluted tubule

Question 59

what kind of cells are macula densa/ what do they sense

Answer 59

chemoreceptors that sense NaCl

Question 60

is renin involved in tubular glomerular effect

Answer 60

no, it only reacts to low Na+

Question 61

which three things determine [renin] in plasma

Answer 61

JG cells receive three inputs: - sympathetic input from external baroreceptors, - intrarenal baroreceptors(afferent arteriole), - signals from macula densa*

Question 62

what does decreased stretch do to renin release

Answer 62

stimulates renin release

Question 63

what does increased stretch do to renin release

Answer 63

inhibits renin release

Question 64

which 3 things are the most important triggers for aldosterone response

Answer 64

- sympathetic stimulation of renal nerves - decreased filtrate osmolarity - decreased BP

Question 65

where is artial natriuretic peptide made

Answer 65

cardiac atria

Question 66

where does artial natriuretic peptide act

Answer 66

cells of several tubular segments

Question 67

what does artial natriuretic peptide cause (3 things)

Answer 67

inhibit aldosterone inhibit Na+ rabsorption increases GFR and Na+ excretion

Question 68

what stimulates atrial natriuretic peptide secretion (3 things)

Answer 68

increased Na+ concentration increase blood volume atrial distension*

Question 69

where is most of the filtered K+ reabsorbed

Answer 69

proximal tubule and loop of henle

Question 70

where can some K+ be secreted

Answer 70

collecting duct

Question 71

where is [K+] in urine regulated

Answer 71

cortical collecting duct

Question 72

what is hyperkalemia

Answer 72

excess K+ in blood

Question 73

what happens with an increase in extracellular K+

Answer 73

stimulate aldosterone production, more K+ in urine

Question 74

what happens with an decrease in extracellular K+

Answer 74

no aldosterone produced, less K+ in urine

Question 75

what does aldosterone do to K and Na and where

Answer 75

stimulates Na reabsorption and K secretion in the cortical collecting duct

Question 76

what does water reabsorption depend on

Answer 76

Na reabsorption