pituitary adrenal axis

Question 1

what class of hormone is cortisol

Answer 1

glucocorticoid

Question 2

where is cortisol synthesised

Answer 2

in the zona fasciculata of the adrenal cortex

Question 3

What stimulates cortisol production?

Answer 3

ACTH released from the pituitary gland

Question 4

what hormone class is aldosterone

Answer 4

mineralocorticoid

Question 5

what is the primary product of chromatin cells in the medulla

Answer 5

epinephrine

Question 6

where are androgens synthesised

Answer 6

zona reticularis

Question 7

where are mineralocorticoids synthesised

Answer 7

zona glomerulosa

Question 9

when hormones are released into the cortex where do they go

Answer 9

flow down into medulla vein

Question 10

what is the difference in short-term and long-term stress response to adrenal medulla

Answer 10

in short-term the adrenal medulla releases epi and norepi
in long-term the adrenal medulla releases glucocorticoids and mineralocorticoids

Question 11

effects of mineralocorticoids

Answer 11

retention of Na and water by kidneys
increased blood volume and pressure

Question 12

effects of glucocorticoids

Answer 12

proteins and fats broken down into glucose => increased blood glucose
suppression of immune system
anti-inflammatory

Question 13

what are all steroid hormones derived from

Answer 13

cholesterol

Question 14

where is ACTH produced

Answer 14

anterior pituitary

Question 15

How is ACTH release regulated by the hypothalamus?

Answer 15

The hypothalamus releases CRH which stimulates the anterior pituitary to secrete ACTH

Question 16

How does negative feedback regulate ACTH release?

Answer 16

Cortisol exerts negative feedback on both the hypothalamus and the anterior pituitary, inhibiting the release of CRH and ACTH when cortisol levels are high.

Question 17

How does ACTH stimulate cortisol production?

Answer 17

ACTH activates the MC2R on adrenal cells, which triggers the production of cAMP, leading to activation of enzymes involved in cortisol biosynthesis.

Question 18

what transports cortisol

Answer 18

Corticosteroid binding globulin

Question 19

where are the enzymes that produce steroid hormones from cholesterol located

Answer 19

mitochondria and SeER

Question 20

How does cortisol affect the liver?

Answer 20

stimulates gluconeogenesis

Question 21

What is cortisol’s effect on muscle tissue?

Answer 21

protein catabolism

Question 22

How does cortisol act on adipose tissue?

Answer 22

stimulates lipolysis

Question 23

How does cortisol exert its effects at the cellular level?

Answer 23

Cortisol binds to intracellular glucocorticoid receptors (GR), which then translocate to the nucleus and regulate the expression of specific genes

Question 24

What happens after cortisol binds to its receptor?

Answer 24

The cortisol-receptor complex binds to glucocorticoid response elements (GREs) in the DNA, either enhancing or repressing transcription of target genes.

Question 25

What is cortisol excess, and what condition is it associated with?

Answer 25

associated with Cushing’s syndrome, where the body produces or is exposed to abnormally high levels of cortisol.

Question 26

What is cortisol deficiency, and what condition is it associated with?

Answer 26

linked to Addison’s disease, where the adrenal glands fail to produce adequate cortisol, leading to a range of symptoms.

Question 27

What are the main causes of Cushing’s syndrome?

Answer 27

Exogenous administration of glucocorticoids Endogenous causes such as pituitary adenomas

Question 28

What are the main causes of Addison’s disease?

Answer 28

autoimmune disease where adrenal cortex attacking antibodies destruct cortex

Question 29

What metabolic effects are seen in Cushing’s syndrome?

Answer 29

hyperglycaemia

Question 30

symptoms of crushing syndrome

Answer 30

moon face weight gain hypertension osteoporosis

Question 31

symptoms of addisons disease

Answer 31

fatigue weight loss hypotension hypoglycaemia

Question 32

what does aldosterone promote

Answer 32

Na retention and K excretion

Question 33

what does prolonged use of glucocorticoids cause

Answer 33

irreversible atrophy of cortisol secreting cells body can no longer produce its own cortisol

Question 34

explain the pituitary adrenal axis leading to insulin secretion

Answer 34

corticotropin releasing hormone (CRH) from hypothalamus stimulates adrenocorticotropic hormone (ACTH) from anterior pituitary this targets the adrenal cortex (zona fassiculata) to secrete cortisol

Question 35

when are cortisol levels highest

Answer 35

morning

Question 36

when might the activity of CRH-ACTH-cotrisol system be enhanced

Answer 36

during stress

Question 37

what role does DHEA have in females

Answer 37

regulates androgen dependent process such as growth of pubic and axillary hair enhancement of pubical growth

Question 38

what controls androgen secretion? what does DHEA inhibit

Answer 38

ACTH gonadotropin releasing hormone

Question 39

what is conns syndrome

Answer 39

hyper secreting adrenal tumour made of aldosterone secreting cells

Question 40

hyper secretion of aldosterone causes

Answer 40

excessive Na retention (hypernatermia) hypokalaemia hypertension

Question 41

what causes the main symptoms in Cushing syndrome

Answer 41

excessive gluconeogenesis too many amino acids converted into glucose

Question 42

what does adrenal androgen hyper secretion cause

Answer 42

adrenogenital syndrome in females causes masculin characteristics in newborn females causes male external genitalia to form

Question 43

where are catecholamines stored and how are they release

Answer 43

stored in chromaffin cells and secreted into blood by exocytosis

Question 44

describe the stress response in relation to catecholamines

Answer 44

hypothalamus stimulates sympathetic nervous system to stimulate epinephrine release from chromaffin cells in adrenal medulla the sympathetic nervous system can also cause vasoconstriction