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1
Q

What stimulates Angiotensin II secretion

A

Angiotensin I availability (which is dependent on Renin)

2
Q

What are the direct effects of Angiotensin II

A
  • *Systemic vasoconstriction (strongest constrictor)
  • *increase Na+ reabsorption and H+ excretion in prox. tubules (acts on kidneys via its self and by activating aldosterone)
  • *Increase aldosterone secretion (on adrenal gland)
  • vasoconstriction –> decreases GFR
  • Increase ADH secretion
3
Q

What are the indirect effects of Angiotensin II

A
  • increase water reabsorption (increase blood volume)
  • increase in Na+ reabsorption
  • increase BP
  • increase thirst (via CNS)
  • Metabolic alkalosis
4
Q

What stimulates aldosterone secretion

A
  • *angiotensin II
  • *Hyperkalemia (high potassium)
  • *decrease plasma [Na+]
  • ACTH (weakest influence)
5
Q

What are the direct effects of aldosterone

A
    • increase Na+ reabsorption in distal tubules and therefore the passive reabsorption of water
    • increase K+ secretion in distal tubules
  • increase H+ secretion in distal tubules
6
Q

What are the indirect effects of aldosterone

A
  • Increase water reabsorption
  • increase BP
  • decrease serum K+
  • Metabolic alkalosis
7
Q

What stimulates ADH secretion

A
    • increased serum osmolarity (ECF)
  • decreased BP/volume
  • Angiotensin II
  • hypoglycemia
8
Q

What are the direct effects of ADH

A
  • *Systemic vasoconstriction
  • *Insertion of aquaporin channels in distal tubules and collecting ducts leading to increased FREE WATER REABSORPTION
  • increase ACTH secretion
9
Q

What are the indirect effects of ADH

A
  • decrease serum Na+, which decreases serum osmolarity
  • increase BP
  • decreases urine output
10
Q

What hormones stimulate reabsorption of Na+ in the kidneys

A

Angiotensin II and aldosterone

11
Q

How is water reabsorption stimulated in the kidneys

A

indirectly stimulated by Angiotensin II and aldosterone

and directly by ADH

12
Q

how is potassium reabsorption stimulated in the kidneys

A

indirectly stimulated by Angiotensin II and aldosterone

13
Q

When levels of coritsol are elevated, how does it behave

A

like aldosterone

14
Q

What prevents reabsorption of K+ in the kidneys

A

aldosterone

15
Q

What drives K+ from ECF to ICF

A
  • insulin

- catacholamines (epiniphrine)

16
Q

What are the major overall effects of Angiotensin II

A
  • increase BP

- increase blood volume

17
Q

What are the major overall effects of aldosterone

A
  • increase BP
  • increase blood volume
  • decrease serum [K+]
18
Q

What are the major overall effects of ADH

A
  • increase BP
  • increase blood volume
  • decrease [Na+]***
19
Q

What stimulates renin secretion

A
  • decrease in BP (renal perfusion pressure)
  • decrease in [NaCl] around macula densa
  • increase efferent SNS activity
  • *Independent of one another
20
Q

What is the rate limiting step in the mechanism of activating angiotensin II

A

the release of renin

*this is very tightly controlled

21
Q

What is the job of renin

A

to hydrolyze angiotensinogen into angiotensin I

22
Q

What inhibits renin

A
  • increase in BP
  • lots of Angiotensin II (which ultimatly increases BP)
  • ANP (atrial natriuretic peptide)
  • *independent of one another
23
Q

When [NaCl] is low around the macula densa what is happening?

A
  • Renin release will be stimulated

- the [ECF] will decrease

24
Q

How is Kenny’s SNS affecting his RAA axis?

A

Kennys hypovolemia and increased HR stimulates increase SNS activity, which increases renin release

25
Q

How does angiotensin II vasoconstrict?

A

promotes increase in intracellular [Ca2+] through actions of phospholipase C and IP3

26
Q

Angiotensin II effects on the CNS

A
  • increases sympathetic NS outflow
    - increase BP
    - increase cardiac output
  • dipsogenic actions (stimulates thirst)
  • Increase ADH release
  • increase ACTH
27
Q

What stimulates thirts

A
  • increase in plasma osmolarity (ECF)
  • decrease blood volume
  • decrease blood pressure
  • increase in angiotensin II
  • dryness of mouth
28
Q

Angiotensin II effects on the kidneys

A
  • decreases GFR due to vasoconstriction
  • promotes Na+ reabsorption in the prox. convoluted tubule
  • inhibits renin secretion
29
Q

What is another name for vasopressin

A

ADH

30
Q

At max. plasma ADH what will happen to urine production?

A

Volume of urine produced will be very low (low urinary flow rate) but the osmolarity of the urine produced will be very high
**Therefore, ADH is directed at water not solute!

31
Q

What is our estimated plasma volume?

A

~ 3 liters

32
Q

How does ADH increase water reabsorption in the distal tubules and collecting ducts?

A

By binding to its receptor and activating aquaporins which allow water to be reabsorbed

33
Q

Normal physiological pH

A
  1. 4 +/- 0.02

* Baby’s don’t have as much control over this as adults

34
Q

bronsted lowry acid

A

Can donate a proton

35
Q

Bronsted lowery base

A

can accept a proton

36
Q

lewis acid

A

can accept a pair of electrons

37
Q

lewis base

A

can donate an electron pair

38
Q

strong acid/base behavior and example

A

complete dissociation occurs (one way arrow with the reaction formula)
ex. HCL —> H+ + Cl- (get two molecules total)

39
Q

what is the pH of a solution if you add 0.2 moles of HCl to 3 L of water?

A

pH= 1.17

40
Q

how to get from pH to [H+]

A

pH= -log[H+]

41
Q

What is the relationship between pKa and Ka

A

inverse relationship (the bigger the Ka the smaller the pKa)

42
Q

[A-] is the conjugate ____ and [HA] is the conjuate _____

A

base and acid

43
Q

What does it mean when the ratio of weak acids is high?

A

it is forced to dissociate

44
Q

Ka and Keq are fixed for what conditions

A

temperature and pressure

45
Q

when the ratio of conjugate base/conjugate acid is one, what does that mean about the pKa and pH

A

pKa= pH

46
Q

is the conjugate acid or base in higher concentration when the pH > pKa and why

A

the base is in higher concentration becasue the conjugate acid is being forced to dissociate into its conjugate base

47
Q

In what ratio will the forms of carbonic acid exist in the ECF? pKa of carbonic acid= 3.77

A

[HCo3-]/[H2Co3] = 4265.79

hint. HH eqn

48
Q

buffer region

A

from pKa -1
to
pKa +1
(buffer region spans +/- 1 pKa unit from when pKa=pH

49
Q

does the acid or base predominate when the pH

A

acid form predominates

50
Q

coordinates of a titration curve

A

Y axis: pH
x axis: mol OH-
each buffer region or platue will occur when pKa=pH

51
Q

Explain the buffer zone and what happens as it reaches the equivalence points

A

when you add conjugate base (with a salt) to a weak acid in a buffer system, you continue to add base until all of the acid form us used up and you only have the new base left. Once it is all used you are at the equivalence point. (you have completely removed your proton)

when you get to pKa=pH you have removed half of the protons from the acid and put them on half of the bases

52
Q

formula for phosphoric acid

A

H3PO4

53
Q

formula of carbonic acid

A

H2CO3

54
Q

formula for acetic acid

A

CH3COOH

55
Q

does concentration of the buffer have any effect on the pH it works at?

A

no, but the concentration of the buffer DOES effect the buffer capacity at which is can resist pH change

56
Q

a normal range for lab data is

A

the mean value +/- 2 SD (includes 95.4% of population) anything outside of 4 SD is defintely abnormal

57
Q

accurate

A

close to the true value

58
Q

precise

A

little variation

59
Q

factors that effect a value besides disease

A

gender, age, position, blood source, time of day, nutritional status, genetics, pregnancy, medications, stress, environment, ethnicity

60
Q

draw table formate for sensitivty, specificty, etc.

A

**

61
Q

sensitivity

A

measures the ability of a test to dect disease in a diseased population
**positivity in the disease
(top row)
**Looking to avoid false negatives

62
Q

specificity

A

measures the ability of a test to dect non-disease in a non-diseased population
**detecting negativity in health
(last row)
**Looking to avoid false positives

63
Q

false positive

A

you test positive for a disease you DO NOT have

64
Q

false negative

A

you test negative for a disease you actually DO have

65
Q

high sensitivity, low specificity will result in

A

more false positives

66
Q

low sensitivity, high specificity will result in

A

more false negatives

67
Q

+ predictive value

A

the true number of positive results in all positive results

68
Q

what is the relationship between the predictive value + and disease prevalence?

A

the PV + will be higher in diseases that are more prevalent

- as disease prevalence increases, PV + is equally huge, and PV- decreases

69
Q

Is there more fluid in the ICF or ECF?

A

ICF

70
Q

compartments of the ECF

A
  1. plasma
  2. interstital fluid
  3. lymphatics
  4. transcellular water
    * plasma and interstital fluid is separated by the plasma membrane
71
Q

TBW is a function of what

A

LBM - our weight is about 60% water (less for F)

mass (kg) x 0.6 = TBW

72
Q

More adipose means what for TBW

A

more fat = less TBW

73
Q

is ECF or ICF more constant over time

A

ICF

74
Q

how much does ECF and ICF contribute to TBW

A

20%- ECF

40%- ICF

75
Q

what indicator do you use when measuring TBW

A

3H20

76
Q

what indictor do you use when measuring ECF Volume

A

14C/inulin (bc doesn’t get into cells)

77
Q

what indicator do you use when measuring plasma volume

A

125I (remains in vasculature)

78
Q

assumptions when calculating fluid volumes with indicatiors

A
  1. indicator dispersed uniformly and only within the compartment of interest
  2. volume of indicator added was negliable to the total volume of the compartment
  3. enough time was allowed for equilibrium to be achieved
  4. the compound added was not metabolized, excreted, or secreted
79
Q

ECF =

A

ECF = Plasma volume + TCW + ISFV

80
Q

total blood volume =

A

total blood volume = plasma volume /(1-Hct)

81
Q

anion gap =

A

[sum of Cations (+)] - [sum of anions (-)]

82
Q

in bulk solution, anions and cations are __

A

equal

83
Q

normal range for an anion gap

A

12-18mEq/L

84
Q

what cations and anions are more prevalent in the ECF

A

Na+, Cl-, HCO3-, glucose

85
Q

what cations and anions are more prevelent in the ICF

A

PO4-, K+, Mg2+