biosynthesis of steroid hormones

Question 1

What does the adrenal medulla produce

Answer 1

catecholamines, norepi and mainly epi

Question 2

what is synthesis of catecholamines regulated by

Answer 2

CRH-ACTH axis

Question 3

ACTH stimulates what

Answer 3

synthesis of DOPA

Question 4

High levels of cortisol have what affect on catecholamines

Answer 4

PMNT enzyme increases, which converts norepi to epi

Question 5

Where is the synthesis of norepi

Answer 5

granules

Question 6

where is the synthesis of epi

Answer 6

in the cytosol

Question 7

What are the 2 enzymes in catecholamine degradation

Answer 7

MAO

COMT catecholamine O methyltransferase

Question 8

When assaying for catecholamines what are you usually measuring

Answer 8

the degradation products in the urine

Question 9

How are adrenergic R classified

Answer 9

potency
downstream signaling pathways
location and density

Question 10

What is the role of activated alpha 1 R

Answer 10

vasc sm mm contraction

Question 11

What is the role of activated alpha 2 R

Answer 11

inhibits norepi and insulin release

Question 12

What is the role of activated B1 R

Answer 12

increase CO

Question 13

What is the role of activated B3 R

Answer 13

increase glucose output and vasodilates

Question 14

constant stimulation of alpha R have what effect on vasculature

Answer 14

chronic venoconstriction

Question 15

what is the main role of cortisol

Answer 15

increase plasma glucose
responds to stress
influences glucose utilization, immune and inflammatory homeostasis

Question 16

What hormones are produced in adrenal cortex

Answer 16

mineralocorticoids
glucocorticoids
Androgens (DHEA)

Question 17

what is the backbone for all steroid hormones

Answer 17

cholesterol

Question 18

what is the first steroid produced from cholesterol

Answer 18

pregnalone

Question 19

What steroids can we get from pregnalone

Answer 19

progesterone via 3 beta hydroxylase

17 alpha hydroxylase can make it 17alpha pregnalone

Question 20

What converts progesterone to deoxy corticosterone

Answer 20

21 hydroxylase

Question 21

what is the purpose of 11 beta hydroxylase

Answer 21

take deoxycorticosterone to corticosterone

Question 22

what can corticosterone become

Answer 22

aldosterone (aldosterone synthase)
regulated by RAAS
cortisol by 17 alpha hydroxylase

Question 23

describe deficiency in 17 alpha hydroxylase

Answer 23

Everything is shunted to mineralocorticoid

cannot produce glucocorticoids or androgens

Question 24

describe deficiecy in 21 hydroxylase

Answer 24

cannot produce mineralocoritcoids and glucocorticoids

shunted into androgens

Question 25

describe deficiency in 11 beta hydroxylase

Answer 25

cannot produce glucocorticoids some mineralocorticoids shunted mainly to androgens

Question 26

What is congenital adrenal hyperplasia

Answer 26

group of autosomal recessive disorders | deficiency in either cotrisol, aldosterone or both

Question 27

When adrogen levels are high what happens

Answer 27

virilization

Question 28

what enzyme deficiencies can lead to high adrenal androgens

Answer 28

21-hydroxylase | 11beta hydroxylase

Question 29

What enzyme deficiency leads to a high mineralocorticoid effect

Answer 29

17 alpha hydroxylase | hypertensive

Question 30

what enzyme deficiency leads to excess deoxycotricosterone

Answer 30

11 beta hydroxylase

Question 31

What are the signs of 21 hydroxylase deficiency

Answer 31

``` salt wasting hyponatremia hyperkalemia hypotension CV collapse virilization ```

Question 32

describe the two types of deficiencies of 21 hydroxylase

Answer 32

total or partial

Question 33

What does the 11 beta hydroxylase do

Answer 33

converts desoxycortisol to cortisol

Question 34

What happens in 11 beta hydroxylase deficiency

Answer 34

loss neg feedback inhibition and ACTH mediated adrenal androgen excess is the result

Question 35

What causes the hypertension in deficient 11 beta hydroxylase

Answer 35

increased secretion of deoxycorticosterone

Question 36

Is there any cortisol in a person with 11 beta hydroxylase deficiency

Answer 36

no

Question 37

how do you differentiate between 11 beta and 21 hydroxylase deficiencies

Answer 37

no salt wasting that you see in 21 hydroxylase

Question 38

what type of mutation is are the steroid hormone deficiencies

Answer 38

autosomal recessive

Question 39

What leads to hypertension and hypokalemia in 17alpha hydroxylase deficiency

Answer 39

excess intermediary steroids with mineralocorticoid activity

Question 40

what would be the aldosterone, K, Na, renin levels would be in someone with 21 hydroxylase deficiency

Answer 40

low aldosterone low Na high K renin is increased

Question 41

17 y/o female, no menses, no pubic hair, no breast development, hypertensive frequent headaches hypokalemia, hypernatremia and metabolic alkalosis, low 17-ketosteroids, serum estrogen, increased progesterone, prenelone and 11 deoxycoricosterone and coricosterone

Answer 41

deficient 17 alpha hydroxylase, partial because later in life