SAIDs

Question 1

zona glomerulosa (outer zone)

Answer 1

produces mineralocorticoid

main: aldosterone
function: electrolyte balance

Question 2

zone fasiculata (middle zone)

Answer 2

produces glucocorticoid

main: hydrocortisone a.k.a. cortisol
function: stress hormone functions to maintain homeostasis following stress

Question 3

cortisol production and HPA axis

Answer 3

hypothalamus produces hormone = corticotrophin hormone

pituitary produces = adrenocorticotrophin hormone

adrenal gland = cortisol (synthesised from cholesterol)

Question 4

hydrocortisone (cortisol)

Answer 4

synthesised from cholesterol in the zone fasiculate.

highly protein bound: alpha 2 globulin a.k.a. corticotrophin binding globulin (CBG)

hormone is increased: during stress and hypothyroidism

reduced + conjugated: in the liver and is water soluble

Question 5

glucocorticoid MOA

Answer 5

2 pathways:
genomic
non genomic

Question 6

genomic; involves intracellular receptors

Answer 6

direct:
alter gene transcription of genes that have GRE
GRE = glucocorticoid response element

indirect: repress activity of other transcription factors
e. g. NF- kB + c- jun/Fos

Question 7

genomic pharmacology

Answer 7

direct:
> transactivate anti inflammatory genes
> transrepress pro inflammatory genes

indirect:
inhibition of transcription factors

Question 8

non genomic pharmacology

Answer 8

glucocorticoids bind to cell surface receptors altering second messenger systems

Question 9

glucocorticoid excess

Answer 9

Cushings syndrome:
ACTH dependent (benign tumour causing excess glucocorticoid)
ACTH independent (excess glucocorticoid drug use)

Question 10

cortisol + aldosterone insufficiency

Answer 10

Addisons disease:
treatment is replacement with cortisol with hydrocortisone or prednisolone and aldosterone replacement with fludrocortisone

Question 11

aldosterone excess

Answer 11

Conn’s syndrome:
can be caused by benign tumour (adenoma) secreting aldosterone

can be caused by malignant tumour (carcinoma) secreting aldosterone

treatment: spironolactone (acts as aldosterone receptor antagonist i.e. does not inhibit aldosterone production)

Question 12

drug induced osteoporosis

Answer 12

glucocorticoids disrupt calcium homeostasis and cause reduced calcium absorption in the GIT.

alter balance between osteoclasts + osteoblasts