Brainscape's Knowledge GenomeTM

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


See full index

231 > Lecture 27: Stress and the adrenal glands > Flashcards

Lecture 27: Stress and the adrenal glands Flashcards

1
Q

What are three classes of hormones released from the adrenal glands?

A
  1. mineralcorticoids
  2. glucocorticoids
  3. catecholamines
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

Where are the adrenal glands?

A

they are bilateral organs above the kidneys

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

What two tissues does the adrenal gland derive from?

A

neural and epithelium

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

How many structures make up the adrenal gland?

A

2

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

What are the names of the structures of the adrenal gland? What percentage of the adrenal gland so these parts make up?

A

There is the cortex which makes up 80% of the adrenal gland encapsulates the medulla which makes up 20% of the gland

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

What cells make up the medulla?

A

chromaffin cells

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

What is significant about the different zones of the adrenal gland?

A

they all produce a different hormone

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

How many zones is the medulla split into?

A

1

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

How many hormones does the medulla secrete?

A

2

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

What are the two hormones that are secreted by the medulla?

A

epinephrine

norepinephrine

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

How many zones is the cortex split into?

A

4

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

How many of the 4 zones of the cortex secrete hormones?

A

3

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

What are the names of the zones in the cortex (from the outside in)?

A

capsule
glomerulosa
fasciculata
reticularis

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

What is the zone in the cortex that doesn’t release hormone?

A

capsule

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

What is the name of the hormone secreted from the glomerulosa on the cortex in the adrenal medulla?

A

aldosterone

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

What is the name of the hormone secreted from the fasciculata on the cortex in the adrenal medulla?

A

cortisol

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

What is the name of the hormone secreted from the reticularis on the cortex in the adrenal medulla?

A

androgens

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

What is the precursor to adrenal cortex hormones?

A

cholesterol

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

From cholesterol, there is a rate limiting reaction. What is this and what does it form?

A

There is a side chain cleavage which converts it to pregnenolone.

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

Can pregnenolone exist for very long?

A

no

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
21
Q

What are the three broad classes of hormones that pregnenolone is converted to?

A
  • glucocorticoids
  • mineralocorticoid
  • sex steroid precursors
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
22
Q

Give two examples of glucocorticoids and where is this located?

A

cortisol
corticosterone
in the zona fasiculata

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
23
Q

Give an example of a mineralocorticoid and where it’s located

A

aldosterone

in the zona glomerulosa

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
24
Q

Give an example of a sex steroid prescursor and where it’s located

A

androstenedione

in the zona reticularis

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
25
Q

What does aldosterone act to do?

A

it acts to maintain fluid volume

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
26
Q

What is the main site of action of aldosterone?

A

kidneys

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
27
Q

How does aldosterone maintain fluid volume?

A

by increasing the reabsorption of sodium and water and increasing the secretion of potassium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
28
Q

What receptor does aldosterone bind to?

A

mineralocorticoid receptors (MR)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
29
Q

What is the direct effect of aldosterone increasing the reabsorption of sodium and water and increasing the secretion of potassium?

A

it increases water retention and increases blood pressure

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
30
Q

Describe the cell signalling of aldosterone

A

Because it is lipophilic, it diffuses into the cell where it binds to the MR. This MR then binds to the DNA to a response element (a promotor) which activates gene transcription of genes then these are converted to proteins

31
Q

Are all adrenal cortex hormones lipophlic?

A

yes because they are precursors of cholesterol

32
Q

Give two examples of the proteins that are synthesised as a result of aldosterone

A

ENaC (Na+ channel)

Na+/K+ ATPase

33
Q

What are the two sides of the cells of the kidney collecting duct called?

A

apical (tubule)

basolateral (interstitium)

34
Q

What is the effect of aldosterone creating ENaC and Na+/K+ ATPase?

A

Na+ enters the cell on the apical side and is then pumped out of the basolateral membrane via the Na+/K+ ATPase. This creates an osmolateral gradient so the H20 flows from the apical side (collecting duct) to the basolateral side (the interstitium)

35
Q

What 4 organs control the production of aldosterone? Is this an indirect or direct affect?

A

heart
kidney
liver
lungs

this is an indirect affect

36
Q

As well as the organs, what else controls the release of aldosterone? Is this an indirect or direct affect?

A

the K+ load

this is a direct affect

37
Q

Describe how the K+ load controls the release of aldosterone

A

The aldosterone is produced by the adrenal glad and there is a direct action on this production from the K+ load. This means that an increase in the K+ load increase plasma K+ which increases aldosterone

38
Q

Describe the steps that allows the kidney, liver and lungs to control aldosterone production

A _______, having ______ ______ and ________ deprivation leads to a _________ in the __ ___ ___ volume. This stimulates the r_________ j________ cells in the kidney to produce _________. The liver releases a___________ and renin stimulates this to be converted into ____________. The lungs produce a __________ __________ which converts ____________ into ________________ and this affects the __________ ___________ and stimulates the production of ______________

A

A haemorrhage, having upright posture and Na+ deprivation leads to a decrease in the ECF volume. This stimulates the renal juxtaglomerular cells in the kidney to produce renin. The liver releases angiotensinogen and renin stimulates this to be converted into angiotensin |. The lungs produce a converting enzyme which converts angiotensin | into angiotensin || and this affects the adrenal gland and stimulates the production of aldosterone

39
Q

Describe how the heart controls the release of aldosterone

A

The heart releases an atrial natriuretic hormone which stops the release of aldosterone from the adrenal gland.

40
Q

What is the name of the substance that is released from the kidneys and converts angiotensinogen to angiotensin |?

A

renin

41
Q

What is the name of the substance released from the liver that is converted to angiotensin | by renin?

A

angiotensinogen

42
Q

What is the name of the enzyme released from the lungs that converts angiotensin | to angiotensin ||?

A

converting enzyme

43
Q

What is the name of the substance that is converted to angiotensin || via converting enzyme?

A

angiotensin |

44
Q

What is the name of the substance that angiotensin | is converted to via converting enzyme?

A

Angiotensin ||

45
Q

Where is cortisol released from?

A

the adrenal gland

46
Q

Describe the release of cortisol

A

Corticotropin releasing hormones reside in the paraventricular nucleus of the hypothalamus and then they project to the median eminence and then stimulate the release of adrenocorticotrophic hormone from the anterior pituitary gland. This stimulates the release of glucocorticoids (such as cortisol) from the adrenal gland

47
Q

Describe the negative feedback of the release of cortisol

A

cortisol feeds-back to the paraventricular nucleus to prevent the release of ACTH from the anterior pituitary gland and to the hypothalamus to stop the release of corticotropin releasing hormone

48
Q

What are the only 2 glucocorticoids and what is the only one present in humans?

A

cortisol
corticosterone

only cortisol is found in humans

49
Q

ACTH is needed for the release of cortisol and it comes from a precursor. What is its name?

A

Proopiomelanocortin

50
Q

Describe the importance of post-translational modifications on the production of ACTH

We have _______ which is transcribed to ______ and then it is converted to a _________ (_________________). On this protein, have encoded several further __________ that then act as _____________. One is ______ and another is γ_______ and β________ so we can see that the precursor makes a lot of different _______ and ________ is one of them. This shows _________-__________ ____________. _________ can be activated by ___________ and ACTH will need to be ______________ because it won’t be there if we don’t have ___________ that _______ it out

A

We have DNA which is transcribed to mRNA and then is converted into a protein (Proopiomelanocortin). On this protein, we have encoded several further proteins that can then act as hormones. One is ACTH and another is γMSH and β LPH so we can see that the precursor makes a lot of different proteins and ACTH is one of them. This shows post-translational modifications. Hormones can be activated by metabolism and ACTH will need to be activated because it won’t be there if we don’t have enzymes that cleave it out.

51
Q

Describe the control of cortisol release

A
  • hypothalamic corticotropin releasing hormone stimulates the release of adrenocorticotropic hormone from the anterior pituitary gland (antidiuretic hormone can also cause ACTH secretion)
  • ACTH acts through melanocortin MC2 receptors in the adrenal gland which increases P450 side-chain-cleavage (cholesterol cleavage to form cortisol).
  • cortisol is released which negatively feedsback to inhibit the release of CRH from the hypothalamus and to stop the release of ACTH from the anterior pituitary gland
52
Q

What are the main actions of cortisol in the body?

  • it stimulates the ______ to generate _________ and to convert ___________ to ____________
  • it stimulates the __________ ____________ to release energy by causing a breakdown of __________________ and __________-_________ ______________
  • it also causes the ____________ to break down ___________ to ___________ ___________ to be converted to glucose in the ______________
  • glucose uptake into the ___________ ___________ is inhibited as the ____________ is inhibited by ____________
A
  • it stimulates the liver to generate glucose (gluconeogenesis) and to convert glycogen to glucose (glycogenolysis)
  • it stimulates the adipose tissue to release energy by causing the breakdown of triglycerides to free-fatty acids
  • it also causes the muscles to break down protein to amino acids to be converted to glucose in the liver
  • glucose uptake into the muscle cells is inhibited as the insulin is inhibited by cortisol
53
Q

What effect does cortisol have on muscles?

A

it maintains muscle function and decreases muscle mass

54
Q

What effect does cortisol have on bones?

A

it decreases bone formation and increases bone resorption

55
Q

What effect does cortisol have on the connective tissue?

A

It decreases the connective tissue so there is less collagen

56
Q

What effect does cortisol have on the immune response?

A

it inhibits inflammatory and immune responses

57
Q

What effect does cortisol have on the heart?

It maintains cardiac ___________, increases _________ tone and decreases ______________ p______________

A

it maintains cardiac output, increases arteriolar tone, decreases endothelial permeability

58
Q

What effect does cortisol have on the maturation of the foetus?

A

it facilitates the maturation of the foetus

59
Q

What effect does cortisol have on the kidneys?

It increases g__________ f_________ and ___________ ____________ ___________

A

it increases glomerular filtration and free water clearance

60
Q

What effect does cortisol have on the brain?

A

it modulates emotional tone and wakefulness

61
Q

Where are catecholamines produced in the adrenal gland?

A

the adrenal medulla (not the cortex)

62
Q

What are two examples of catecholamines?

A

epinephrine (adrenaline)

norepinephrine (noradrenaline)

63
Q

Describe the sympathetics control of the adrenal medulla

A

The adrenal gland is under sympathetic control of the sympathetic nervous system. The post-ganglionic neurons project to the adrenal gland and release catecholamines.

64
Q

What are the 4 cardiovascular effects of adrenaline?

  • increasing __________ ____________ (by acting on _______ receptors)
  • increasing __________ ___________ (by acting on _________ receptors)
  • dilating ___________ ____________ around _____________ (by acting on _____________ arterioles)
  • by constricting other ____________ (by acting on _____________ receptors)
A
  • increasing cardiac contractility (by acting on β1 receptors)
  • increasing heart rate (by acting on β1 receptors)
  • dilating smooth muscle around arterioles (by acting on β2 arterioles)
  • by constricting other arterioles (by acting on α1 receptors)
65
Q

What is the main effect of adrenaline?

A

to shunt blood to exercising muscles and the brain and away from other tissues

66
Q

What are the metabolic effects of adrenaline?

  • it stimulates the production of _____________ and the conversion of _____________ to ____________ in the ___________
  • it inhibits the action of ___________ so glucose is not taken up by the __________ or _________ cells
  • it stimulates ____________ breakdown in the muscle and _________ ___________ up-take by the __________
  • it stimulates the release of __________ __________ _____________ from the __________ tissue
  • it stimulates the release of _______________ from the liver
A
  • it stimulates the production of glucose (gluconeogenesis) and the conversion of glycogen to glucose (glycogenolysis) in the liver
  • it inhibits the action of insulin so glucose is not taken up by the muscle or fat cells
  • it stimulates glycogen breakdown in the muscle and lactic acid up-take by the liver
  • it stimulates the release of free fatty acids from the adipose tissue
  • it stimulates the release of ketoacids from the liver
67
Q

What is stress?

A

the sum of the biological reactions to any adverse stimulus, physical, mental or emotional, internal or external, that disturbs homeostasis

68
Q

Which is faster acting, adrenaline or cortisol?

A

They both have metabolic affects (which are relatively slow) but adrenaline is faster acting because it gets blood to the areas where it is needed

69
Q

Which hormone’s main effect is vascular changes?

A

adrenaline

70
Q

Which hormone’s main effect is metabolic changes?

A

cortisol

71
Q

What two things happen in the fight-or flight-response?

A

adrenal cortex releases cortisol for energy mobilisation and the adrenal medulla releases adrenaline for vascular changes

72
Q

Chronic stress increases cortisol. What is the effect of this?

  • Decreases __________ function
  • increases risk of _________ and ____________
  • worsens ____________ due to anti-insulin effects
  • possibly increases __________ death rate
  • might enhance _____________ and ____________ (increased blood lipids, increased cardiac work)
  • decreased ________ density
  • i__________
A
  • Decreases immune function
  • increases risk of infection and cancer
  • worsens diabetes due to anti-insulin effects
  • possibly increases neuronal death rate
  • might enhance artherosclerosis and hypertension (increased blood lipids, increased cardiac work)
  • decreased bone density
  • infertility
73
Q

What is Cushing’s syndrome?

A

Where there is an overproduction of cortisol which causes lots of abdominal fat and means you are prone to cancer, bruises and infections

231 (41 decks)

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