Endocrinology: Adrenal Glands

Question 1

the ____ is important in pregnancy, lies between the ___ and ____ in the fetus. Very thick and rich source of ______, where it is converted to estrogen in the _____

Answer 1

fetal adrenal zone
cortex and medulla
androgens
placenta

Question 2

glucocorticoids are released from the _____ layer of the cortex

Answer 2

both the zona fasciculata and zona reticularis

Question 3

mineralocorticoids are released from the ______

Answer 3

zona glomerulosa

Question 4

sex hormones/androgens are released from the ____

Answer 4

zona reticularis and zona fasciculata

Question 5

______ is a group of modified post-ganglionic sympathetic nerve cells

Answer 5

adrenal medulla

Question 6

adrenal medulla is composed of ____ cells

Answer 6

chromaffin cells (nerve cells without axons)

Question 7

the adrenal medulla releases ____ and ____

Answer 7

80% EPI and 20% NE

Question 8

EPI and NE are derived from ______

Answer 8

tyrosine

Question 9

EPI/NE have similar effects at _____ receptors

Answer 9

beta1

Question 10

EPI more selective at _____

Answer 10

beta2

Question 11

5 big effects of EPI

Answer 11

1) mediate the body responses to stress (fight or flight)
2) increase cardiac output, blood flow (selective vasodilation/vasoconstriction)
3) stimulates glycogen/fat breakdown = fuels
4) stimulate insulin/glucagon both
5) enhances airway/respiration and CNS alertness

Question 12

EPI adjusts blood flow: selective vasodilation in _____ via ____ receptor, and vasoconstriction in ___, ____, and ___

Answer 12

muscle —- beta2

gut, skin, and kidney —- alpha 1 and alpha 2 (digestive organs)

Question 13

NE more important in ______ situations

Answer 13

non-emergency (adrenal source during emergency, autonomic system source during non-emergency)

Question 14

______ is an adrenomedullary dysfunction in which there is an overproduction of catecholamines (mainly NE). Describe the pathophysiology. What is a specific diagnostic test?

Answer 14

• pheochromocytoma
• chromaffin cells from the neural crest migrate during embryogenesis all over the body to form nerve tissues, and can form pockets of chromaffin cells acting like small adrenal medulla glands all over body.
• measuring the NE/EPI levels

Question 15

_____ is symptom that has the most frequent occurrence in pheochromocytoma. Why?

Answer 15

HTN

NE is secreted more then EPI, thus more vasoconstriction effects that leads to HTN.

Question 16

draw out the adrenal steroid biosynthesis - aldosterone

Answer 16

CHL — PREG —- PROG — 11 - deoxycorticosterone —- corticosterone —- aldosterone

Question 17

draw out the adrenal steroid biosynthesis - cortisol

Answer 17

CHL — PREG —17-hydroxypreg —- 17-Hydroxyprogesterone —- deoxycortisol —– cortisol

Question 18

draw out the adrenal steroid biosynthesis - testosterone and estradiol

Answer 18

CHL — PREG — 17 - HYDROXYPREG —- DEHYDROEPIANDROSTERONE (DHEA) —- ANDROSTENEDIONE —- TESTOSTERONE —– ESTRADIOL

Question 19

____ is main compound in non-pregnant women

Answer 19

estradiol

Question 20

____ is main compound in pregnant women

Answer 20

estriol

Question 21

important enzyme that cleaves off side chain from testosterone to make estrogen

Answer 21

aromatase

Question 22

____ is the rate limiting step in adrenal steroid biosynthesis

Answer 22

CHL —> Pregnenalone

Question 23

what is the major control mechanism for each zone of the adrenal cortex?

Answer 23

Z. glomerulosa —> renin-angiotensin system
Z. fasciculata –> ACTH
Z. reticular –> ACTH

Question 24

Theoretically: how could Z. fasciculata and Z. reticularis grow larger than Z. glomerulosa?

Answer 24

ACTH is trophic, so could influence growth of fasciculata and reticularis; whereas angiotensin is NOT trophic

Question 25

how does cortisol travel in blood? bound vs unbound

Answer 25

10% free

75% on CBG (transcortin) and 15% on albumin

Question 26

how does aldosterone travel in the blood?

Answer 26

40% free

10% on CBG (transcortin) and 50% on albumin

Question 27

how does DHEA-sulfate travel in blood?

Answer 27

2% free

98% on albumin

Question 28

what could lead to an increase in free steroid hormones in blood?

Answer 28

underproduction of plasma proteins by liver

OR over secretion of hormone

Question 29

____ most active of secreted adrenal steroid hormones. WhY?

Answer 29

aldosterone bc is travels in blood 40% free (much higher level of unbound hormone than others)

Question 30

what are the two methods of metabolism of adrenal steroids?

Answer 30

1) reduction of biological activity (reduction of steroid molecule)
2) conjugation with glucuronides/sulfates in order to increase polarity and water solubility to allow for renal excretion

Question 31

DHEA travels in blood with sulfate (which increases its water solubility) why isn’t it excreted by kidneys in great amounts?

Answer 31

bc it travels 98% attached to albumin in blood

Question 32

_____ receptor has greater affinity for NE than for EPI

Answer 32

alpha 1 and alpha 2

Question 33

second messenger and general effects of alpha 1 receptor?

Answer 33

activates IP3, DAG, and calcium
EXCITATORY
FOUND ON MOST SYMPATHETIC TARGET TISSUES

Question 34

second messenger and general effects of alpha 2 receptor?

Answer 34

inhibits cAMP
INHIBITORY
found in digestive organs

Question 35

second messenger and general effects of beta1 receptor?

Answer 35

activates cAMP
EXCITATORY
found in heart

Question 36

second messenger and general effects of beta2 receptor?

Answer 36

activates cAMP
INHIBITORY
found in smooth muscles of arterioles and bronchioles