Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

brs2 > renal regulation of water and acidbase balance > Flashcards

renal regulation of water and acidbase balance Flashcards

1
Q

what is osmotic pressure dependent on

A

total number of solute particles

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

how can we calculate osmolarity

A

concentration x no. of dissociated particles

osm/l

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

what are some form of unregulated water loss

A

sweat faeces
vomit
water evaporation from skin

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

what is regulated water loss

A

renal regulation - urine production

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

what is positive water balance

A

happens when there is high water intake
causes increase in ecf vol
decreased na+ and decreased osmolarity
.. therefore kidneys produce hyposmotic (dilute) urine production

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

what is negative water balance

A

happens when low water intake
decreased ecf vol but increased na+ and osmolarity
kidneys produce hyperosmotic urine and triggers thirst

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

where is 67% of water reabsorbed in kidneys

A

proximal convoluted tubule

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

what % of water is reabsorbed at thin descending limb

A

15%

no na or cl reabsorbed

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

is any water reabsorbed at ascending limb

A

no only na and cl reabsorbed

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

why does medullary interstitium need to be hyperosmotic

A

for water reabsorption to occur from loop of henle and collecting ducts

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

what are vasa recta

A

series of blood capillaries that surround your nephron mainly in medullary region

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

how is urea transported out collecting duct into medullary interstitium

A

via uta3 and uta1 transporters

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

where can urea travel to after leaving the collecting duct

A

into vasa recta via utb1 transporter or into thin ascending limb via uta2 transporter

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

what is the reason behind why urea increases interstitium osmolarity

A

urine concentration occurs

urea excretion requires less water

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

what is vassopressins role in urea

A

boosts uta1 and uta3 numbers and increases permeability of collecting duct for urea

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

what is the main function of adh/vasopressin

A

promote water reabsorption from collecting duct

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

where is vasopressin/adh produced

A

hypothalamus - neurons in supraoptic and praventricular nuclei

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

what are some stimulatory factors that influence adh production and release

A 
increase in plasma osmolarity
hypovolemia
decrease in blood pressure
nausea
angiotensin 2
nicotine
19
Q

what are some inhibitory factors influencing adh production and release

A 
decrease in plasma osmolarity
hypervolemia
increase in blood pressure
ethanol
atrial natriuretic peptide
20
Q

what % change is required for detection by baroreceptors for adh release/inhibition

A

5-10%

21
Q

what is the mechanism of adh

A

adh binds to v2 receptor on basolateral membrane of collecting duct
activates g coupled protein mediated signalling cascade
activates protein kinase A
and increases secretion of aqp2 which are inserted into apical membrane

22
Q

what is diuresis

A

increased dilute urine excretion

23
Q

what is antidiuresis

A

concentrated urine in low volume excretion

24
Q

treatment for syndrome of inappropriate adh secretion (siadh)

A

non-peptide inhibitor of adh receptor - conivaptan and tolvaptan

25
Q

what is the treatment of nephrogenic diabetes insipidus

A

thiazide diuretics and nsaids

26
Q

what is the role of kidneys in acidbase balance

A

secretion and excretion of h+
reabsorption of hco3-
production of new hco3-

27
Q

what is the neutral ecf hco3-

A

~ 350mEq or 24mEq/L

28
Q

what % of bicarbonate ions are reabsorbed by kidneys

A

almost 100%
around 80% in pct
10% in thick ascending limb

29
Q

how are h+ ions reabsorbed in pct

A
  1. via na+h+ antiporter

2. h+ atpase pump

30
Q

how are bicarbonate ions reabsorbed into blood

A

via na+hco3- symporter

31
Q

what are the 2 different cells present in dct and collecting duct

A

alpha intercalated cell

beta intercalated cell

32
Q

what is role of alpha intercalated cell

A

hco3- reabsorption and h+ secretion

33
Q

what is the role of beta intercalated cells

A

hco3- secretion and h+ reabsorption

34
Q

how are new bicarbonate ions produced

A

in proximal convoluted tubule glutamine is converted into 2 molecules of ammonia and 1 divalent ion which gives rise to 2 hco3- ions which are reabsorbed
ammonia re-enters blood circulation reaches liver and gets converted into one urea ion and one proton ion
THEREFORE ammonia must be excreted from body via na+h+ antiporter and becoming ammonia gas and binding with proton ion into tubular fluid

35
Q

how are bicarbonate ions produced in dct and collecting duct

alpha intercalated cells

A

proton ion is neutralised with a phosphate ion
hco3- is gained
travels into blood via cl-hco3- antiporter

36
Q

what are the characteristics of metabolic acidosis

A

low hco3-

low ph

37
Q

what is the compensatory response to metabolic acidosis

A

increased ventilation

increased hco3- reabsorption and production

38
Q

what are the characteristics of metabolic alkalosis

A

high hco3- and high ph

39
Q

what is the compensatory response to metabolic alkalosis

A

decreased ventilation

increased hco3- excretion

40
Q

what is respiratory acidosis

A

high pco2

low ph

41
Q

what is the compensatory response to respiratory acidosis

A

acute - intracellular buffering

chronic - increase in hco3- reabsorption and production

42
Q

what is respiratory alkalosis

A

low pco2 and high ph

43
Q

what is the compensatory response to respiratory alkalosis

A

acute - intracellular buffering

chronic - decrease in hco3- reabsorption and production

brs2 (65 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions