Lecture 10- Renal- Ion and Water balance Flashcards

1
Q

after filtration, tubular fluid is subject to reabsorption or secretion. these processes involve transport of substances across the tubular epithelial cells in a nephron. there are 2 modes of transport, what are they?

A

transcellular- molecules move through tubular cells

paracellular- molecules move between tubular cells

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

… diffusion requires a specific membrane protein and they can be 3 different types

A

uniporter
symporter
antiporter

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

… transport is against the gradient and is coupled with ATP

A

active

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

sodium can be reabsorbed in all but this segment of the nephron

A

thin descending limb of loop of henle

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

you get pretty much 100% of reabsorption of glucose and amino acids in the ….

A

proximal tubule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

there is a about 65% (2/3) reabsorption of Na in the ….

A

proximal tubule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

about … % of Na is reabsorbed in the thin ascending limb

A

7

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

about …% of Na is reabsorbed in the thick ascending limb

A

20

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

about … % of Na is reabsorbed in the distal convoluted tubules

A

5

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

about …% of Na is reabsorbed in the collecting ducts

A

2-3

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

4 ways sodium is reabsorbed in the proximal tubule

A
  1. symporters with glucose
  2. active transport on basal side to keep intracellular sodium low
  3. moves with water and other solutes paracellularly
  4. Na/H antiporter which is indirectly associated with bicarb reabsorption
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

are drugs freely filtered?

A

no, they are too big, must be secreted in the proximal tubule

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

the proximal tubule has …. for organic cations and anions (drugs)

A

transporters

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

drugs are commonly bound to …. so they are not filtered at the glomerulus and must be secreted in order for them to be excreted in the urine

A

plasma proteins

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

in the loop of henle, … of filtered NaCL and … of water is reabsorbed

A

25%

15%

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

the descending thin limb is … to salt but … to water

A

impermeable

permable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

the ascending thin limb is … to salt but …. to water

A

permeable

impermeable

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

reabsorption in the thin descending and ascending limbs is ….

A

passive

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
19
Q

in the ascending limb, fluid becomes … due to …. symporter in apical membrane and …. in basolateral membrane

A

diluted

Na/K/2Cl

Na/K ATPase

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
20
Q

fluid leaving the loop is… but the renal … mechanism has established an … gradient required for formation of hyperosmotic urine.

A

hypoosmotic
countercurrent
osmotic

21
Q

concentration of the tubular fluid will occur in the …. if …. is present

A

collecting duct

ADH (vasopressin)

22
Q

the initial segment of the distal tubule reabsorbs about …% of filtered NaCl via a …. symporter in apical membrane and … in basolateral membrane

A

Na/Cl

Na/K ATPase

23
Q

sodium reabsorption in the latter half of the distal tubule and collecting duct is …

24
Q

there are 2 types of cells in the collecting duct and late distal tubule

A

principal cells that have epithelial sodium channels (ENaC) that reabsorb Na and secrete K

intercalated cells involved with acid-base balance; can also reabsorb K

25
ADH (vasopressin) is released from the ...
posterior pituitary
26
ADH increases the ... of the late distal tubuler and the collecting duct to water by increasing.... into the apical membrane (basolateral membrane is freely permable to water)
permeability aquaporins
27
the release os ADH is stimulated by changes in .... of body fluids and changes in ...
osmolality blood volume/pressure
28
ADH responds to an osmolality above a set point of ...mOsm/kg H2O
275-290
29
.... baroreceptors in the LA and Pulm vessels respond to a ... in blood volume and this stimulates ADH secretion
low pressure decrease
30
... baroreceptors in aortic arch and carotid sinus respond to a .... in blood pressure and this stimulates ADH secretion
high pressure decrease
31
ADH also increases permeability of medullary collecting duct to...
urea
32
if ADH is low, solutes are reabsorbed in distal tubule and collecting duct but no water reabsorption so urine is as dilute as ...
50 mOsm/kg H2O
33
if ADH is high, water is reabsorbed as passes through collecting duct and urine can be concentrated up to ...
1200 mOsm/kg H2O
34
the renin-angiotensin-aldosterone system stimulates events that increase reabsorption of .... to combat volume...
Na and water contraction (low BV)
35
renin converts...
angiotensinogen to angiotensin I
36
Angiotensin I is converted to angiotensin II by ....
angiotensinogen converting enzyme (ACE)
37
what are the 4 effects of angiotensin II?
vasoconstriction stimulate release of ADH increase sympathetic activity stimulate aldosterone secretion
38
renin is released in response to a drop in ...., decreased .... delivery to the macular densa or ... input to the juxtaglomerular cells
perfusion pressure NaCl sympathetic
39
aldosterone from the ... acts to increase .... reabsorption in the distal tubule and collecting duct by increasing ...
adrenal cortex NaCl transport protein synthesis
40
... are hormones that are secreted when the heart dilates (during volume expansion)
natriuretic peptides
41
atrial natriuretic peptide is from the ... | brain natriuretic peptide is from the ...
atria ventricles
42
are aldosterone's effects immediate?
no
43
4 effects of natriuretic peptides
vasodilation of afferent arterioles vasoconstriction of efferent arterioles inhibition of renin/aldosterone inhibition of ADH secretion
44
net effect of natriuretic peptides is to increase secretion of ... and ...
NaCl and water
45
the main location where we see a decrease in Na reabsorption due to natriuretic hormones is in the ....
proximal tubules
46
hypokalemia will .... membrane voltage
hyperpolarize
47
hyperkalemia will ... membrane voltage
depolarize
48
ingested K+ is ... shifted into cells and this is mediated by ... , ... and ...
fast insulin, epi, aldosterone
49
kidneys typically excrete ...% of ingested K+
90-95%