Steroid hormones

Question 1

Corticosteroids

Answer 1

Glucocorticoids (cortisol)- zona fasciculata
Mineralocorticoids (aldosterone)- zona glomerulosa
Androgens (Androstenedione)- zona reticulares

Question 2

Sex hormones

Answer 2

Estrogen -ovaries

Androgen - testis

Question 3

Cholesterol -> Aldosterone

Answer 3

C - p450 scc -PREGENOLONE - 3bhsd - PROGESTERONE - 21ohase - 11DEOXYCORTICOSTERONE - 11ohase - CORTICOSTERONE - aldosterone synthase - ALDOSTERONE

Question 4

Cholesterol -> Cortisol

Answer 4

C - p450 scc - PREGENOLONE - 17ohase - 17 OH PREGENOLONE - 3bhsd - 17 OH PROGESTERONE - 21 ohase - 11 DEOXYCORTISOL - CORTISOL

Question 5

Cholesterol -> Estrone

Answer 5

C - p450 scc - PREGENOLONE - 17ohase - 17 OH PREGENOLONE - 17,20 lyase - DHEA - 3bhsd - ANDROSTENEDIONE - aromatase - ESTRONE

Question 6

Cholesterol -> Testosterone (Estradiol, DHT)

Answer 6

C - p450 scc - PREGENOLONE - 17ohase - 17 OH PREGENOLONE - 17,20 lyase - DHEA - 3bhsd - ANDROSTENEDIONE - 17bhsd - TESTOSTERONE (- 5alfa reductase - DHT) (- aromatase - ESTRADIOL)

Question 7

stAR

Answer 7

steroidogenic acute regulatory protein
transport proteins, regulates cholesterol transfer within the mitochondria
rate-limiting step in the production of steroid hormones
primarily present in steroid-producing cells (theca cells, luteal cells, Leydig cells and cell types in the adrenal cortex)
cAMP inhibits it

Question 8

Aldosterone effects

Answer 8

receptor: mineralocorticoid receptor
intracellular localization
receptor activation- modulates gene expression
promiscuity
prereceptor specificity
Na+ reabsorption, K+ secretion, H+ secreation

Question 9

Excess aldosterone / aldosterone deficiency

Answer 9

Excess:
-hypertension, low K+, low H+

Deficiency:
-loosing salt + water, high K+, high H+

Question 10

Cortisol effects

Answer 10

carbohydrates:

• glucose oxidation decrease
• gluconeogenesis increase
• glycogen synthesis increase

lipids:

• LPL increase
• HSL increase

proteins: proteolysis
other: immunosuppression

Question 11

Excess cortisol / cortisol deficiency

Answer 11

excess:
impared glucose tolerance
obesity
muscle atrophy
livid striae
osteoporosis
propensity for infections

Deficiency:
low BP, dehydration, K+ high, Na+ low
impaired hair growth
exhaustion

Question 12

Testosterone vs Dihydrotestosterone

Answer 12

Testosterone:
in testis
spermatogenesis
psychosexual identity
protein synthesis in muscle
maile voice
male type hair growth

DHT:
in male xternal organs
development and function of prostate
hair growth
baldness
more efficient

Question 13

5 alpha reductase deficiency

Answer 13

XY, testis
normal plasma testosterone but decreased DHT
female, mixed external organs

Question 14

Theca interna cells and granulosa cells

Answer 14

follicular phase
theca interna:
cholesterol -> androstenedione
LH stimulates

granulosa:
cholesterol -> estradiol
FSH stimulates

Question 15

Lutein cells

Answer 15

corpus luteum

cholesterol -> progesterone

Question 16

Polycystic Ovary syndrome

Answer 16

more theca cells, LH receptors and higher Androstenedione production -> HYPERANDROGENISM
oligo-/anovulation
polycystic morphology

Question 17

SERM

Answer 17

selective estrogen receptor modulator
interaction with ER
agonist/antagonist
tissue-specific interactions with coactivators/-repressors

Question 18

Congenital adrenal hyperplasia

Answer 18

defect in cortisol synthesis
21 OHase/ 11OHase deficiency
1:14000
no cortisol to suppress ACTH secreation -> hyperplasia + production of excess androgens