Adrenal Physiology Flashcards Preview

Endocrine > Adrenal Physiology > Flashcards

Flashcards in Adrenal Physiology Deck (68)
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1
Q

3 layers of adrenal cortex

A

glomerulosa, fasciculata, reticularis

2
Q

glomerulosa makes ___

A

aldosterone

3
Q

fasciulata produces ____

A

glucocorticoids

4
Q

reticularis produces ____

A

androgens

5
Q

medulla produces _____

A

adrenaline

6
Q

GFR salt sugar sex

A

mnemonic for adrenal cortex layers

7
Q

Adrenocorticol hormones are produced where?

A

p450 in mitochondria and smooth ER of adrenal gland

8
Q

Rate limiting step in steroidgenesis is ____

A

scc enzyme cleavage of cholesterol to pregnenolone by CYP11A1

9
Q

Corticosterone is converted to aldosterone by

A

aldosterone synthase –> glomerulosa cells only

10
Q

Aldosterone is released in response to (3) ____

A

increased: angiotensin 2, serum potassium, and ACTH

11
Q

Cortisol is released in response to (2) ____

A

increased: ACTH and arginine vasopressin

12
Q

Androgens are released in response to ____

A

increased ACTH

13
Q

Norepi and epinephrine are released in response to _____ and its synthesis is dependent on high local concentrations of _____

A

sympathetic nervous system activation and cortisol

14
Q

Aldosterone binds to ____ receptor to regulate ___ (2)

A

mineralocorticoid: blood volume and salt/water homeostasis

15
Q

Cortisol binds to ____ receptor to regulate ____ (2)

A

glucocorticoid receptor: energy balance, cv, metabolic, immune homeostasis

16
Q

Androgens bind ____ receptor and regulate ___

A

androgen: pubarche

17
Q

norepi/epi bind ___ receptors to regulate ___ (2)

A

adrenergic: cv and bronchial dilation

18
Q

______ senses blood volume, salt concentration in kidney

A

juxtaglomeruler cells

19
Q

Renin is released in response to _____ (2)

A

decreased afferent arteriole volume (low renal perfusion) and decreased distal tubule sodium concentration (tubuloglomerular feedback)

20
Q

Renin is decreased in response to ____ (2)

A

increased afferent arteriole volumea nd increased distal tubule sodium concentration

21
Q

Potassium and angiotensin II sstimulate _____ in the zona glomerulosa

A

aldosterone synthetase

22
Q

Renin

A

converts angiotensin to angiotensin I

23
Q

ACE

A

converts angiotensin I to angiotensin II

24
Q

Effect of aldosterone

A

increased Na reabsorption/water absorption, K+ and H+ secretion –> increase blood volume, decrease blood potassium concentration

25
Q

Increased circulating K induce production of aldosterone which promotes Na reabsorption in exchange for K in the _______ of the nephron

A

distal tubule and collecting duct

26
Q
  • feedback for renin system
A

increase in BP turns off renin production and reduces production of vasoconstrictor angiotensin ii

27
Q

T/F angiotensin ii induces production of aldosterone via direct effect on adrenal gland.

A

T

28
Q

T/F cortisol has negative feedback on both ACTH and CRH

A

T

29
Q

Stimulants of ACTH

A

CRH, vasopressin, inflammation

30
Q

ACTH specific receptor is _______ on _____

A

melanocortin 2 receptor on adrenal tissue

31
Q

ACTH receptor functions

A

increase LDL receptors to bring in more cholesterol for steroid hormones, activate CYP11A1 for cholersterol scc

32
Q

T/F ACTH can function as melanocortin

A

T –> conserved sequence which allows it to activate melanocortin 1 receptor on melanocytes –> high ACTH can stimulate pigment production

33
Q

T/F cortisol rapidly declines after awakening

A

T

34
Q

At what time of day do we measure cortisol in order to determine adrenal insufficiency

A

7-8am

35
Q

At what time of day do we measure cortisol in order to determine adrenal overactivity

A

midnight

36
Q

Cortisol effect on: liver

A

gluconeogenesis, decrease glucose uptake

37
Q

Cortisol effect on: skeletal muscle

A

release AA, insulin resistance (Blocks glucose uptake)

38
Q

Cortisol effect on: immune

A

decrease macrophage, T cell, mast cell activity (antihistamine)

39
Q

Cortisol effect on: bone

A

increase osteoclast, decrease calcium absorption –> osteoporosis

40
Q

Cortisol effect on: adipose

A

release ffa and glycerol

41
Q

Cortisol effect on: heart

A

increase bp via vasoconstriction, increase adrenergic receptor responsiveness

42
Q

Cortisol effect on: vascular smooth muscle

A

vasomotor tone, responsiveness to vasoconstrictors

43
Q

Cortisol effect on: adrenal medulla

A

epinephrine synthesis (PNMT activation)

44
Q

T/F mineralocorticoid receptor has more affinity for cortisol than aldosterone

A

T

45
Q

11beta HSD2

A

converts cortisol to cortisone (shunt) for mineralocorticoid rich tissue –> ensures aldosterone can have an effect in tissues like kidney

46
Q

11betahsd1

A

reverses 11betahsd2 in tissues like liver to ensure cortisol has more impact

47
Q

licorice moa

A

inhibits 11betahsd2 –> lots of cortisol –> hypertension, hypokalemia (psuedohyperalodsteronism)

48
Q

adrenal androgens (3)

A

dhea, dheas, androstenedione

49
Q

T/F increase in adrenal androgens with age

A

T

50
Q

T/F andrenarche begins years before gonadarche

A

T

51
Q

In peripheral tissues, androstendione is converted to ____ (2)

A

testosterone and estrone

52
Q

main site of androgen production in women

A

adrenals

53
Q

main site of androgen production in men

A

testes (adrenals are minor)

54
Q

Adrenal medulla receives input form SNS through preganglionic fibers from _____ spinal cord

A

thoracic

55
Q

T/F medulla lacks synapses from postganglionic fibers

A

T –> releases secretions directly into blood

56
Q

Rate limiting step in catecholamine synthesis

A

tyrosine –> dopa via tyrosine hydroxylase

57
Q

T/F cortisol promotes epinephrine synthesis

A

T –> upregulates PNMT for production of epinephrine from norepinephrine

58
Q

epi/norepi production ratio in adrenal medulla

A

80/20

59
Q

Metanephrines

A

not nuclear receptors–> surface membrane receptors

60
Q

T/F catecholamines and metanephrines have a short half life in blood

A

T –> signal through second messenger systems –> not nuclear receptors

61
Q

Location: alpha 1 adrenoceptor

A

arterial/venous vasculature: increase IP3 (vasoconstriction, increased bp)

62
Q

Location: alpha 2 adrenoceptor

A

arterial/venous vasculature and nerve terminals: decrease cAMP

63
Q

Location: beta 1 adrenoceptor

A

heart, juxtaglomerular apparatus: increase cAMP

64
Q

Location: beta 2 adrenoceptor

A

heart, skeletal muscle vasculature, bronchial smooth muscle: increase cAMP –> bronchodilation, vasodilation)

65
Q

__________ the principal mineralocorticoid, is produced in the ______ and released in response to ____ and ____ and acts on the collecting tubule to increase sodium reabsorption in exchange for _____ and ___ ion, therby restoring _____ and lowering serum ____ concentrations

A

Aldosterone, zona glomerulosa, hyperkalemia and angiotensin II/ACTH, +/H+, intravascular volume, and lowering serum potassium

66
Q

______, the principal glucorticoid is produced in the _______ and is released in response to ____, acting to maintain serum ____ concentration, maintain vascular _____, and to attenuate ______

A

cortisol, fasciularis/reticulata, ACTH, serum glucose, vascular resistance, inflammatory/immune/wound repair response

67
Q

____ (3) , the principal androgens from the adrenals are produced in ____ and released in response to ____ and ____ is converted in peripheral tissues to ____ and ____, sex hormones.

A

DHEA,DHEAS, and androstenedione, zona reticulata, ACTH, androstenedione to testoerone and estrone

68
Q

_____ (2) are the principal catecholamines and produced in the ______ and released in response to ____ stimuli to produce _____ and _____. ___ also increases ___ production by stimulating PNMT.

A

norepi/epi in the medulla, SNS stimuli to produce bronchial dilation and vascular resistance, cortisol increases epinephrine production