Physiology of Adrenal Glands

Question 1

What is the origin of adrenal medulla?

Answer 1

Neuroectodermal origin

Question 2

What does adrenal medulla secrete?

Answer 2

Catecholamines, epi and NE

Question 3

What is the origin of adrenal cortex?

Answer 3

Mesodermal origin

Question 4

Adrenal cortex releases hormones that are colelctively known as

Answer 4

corticosteroids

Question 5

ZG will release

Answer 5

mineralocorticoids

Question 6

ZF and ZR will release

Answer 6

glucocorticoids and androgens

Question 7

ACTH will form due to processing the

Answer 7

POMC peptide

Question 8

Alpha MSH is involved in

Answer 8

pigmentation of skin and appetite regulation

Question 9

Beta endorphin is an endogenous opiate that can

Answer 9

inhibit pain sensitivity

Question 10

Transcortin =

Answer 10

cortisol binding globulin

Question 11

Most cortisol will bind to

Answer 11

CBG (cortisol binding globulin)

Question 12

60% of aldosterone binds to

Answer 12

plasma proteins

Question 13

Once adrenocortical hormones are released from plasma proteins, it will diffuse into

Answer 13

cells and bind to intracellular receptor

Question 14

Steroid-receptor dimerization will occur and this complex will bind to

Answer 14

Glucocorticoid response elements (GRE)

Question 15

Cortisol undergoes what type of release?

Answer 15

Pulsatile- highest in morning

Question 16

Exogenous glucocorticoids are also given as

Answer 16

immunosuppressants

Question 17

What is the rate limiting step in synthesis of corticosteroids?

Answer 17

Cholesterol desmolase

Question 18

What can stimulate cholesterol desmolase?

Answer 18

ACTH

Question 19

All adrenal cortex hormones are derived from what?

Answer 19

Cholesterol

Question 20

Most of the cholesterol is received via

Answer 20

blood stream

Question 21

Fasciculata/reticularis contains

Answer 21

17,20-lyase to make androgen

Question 22

Gomerulosa contains _________ so that aldosterone can be made.

Answer 22

aldosterone synthase

Question 23

Low-density lipoprotein receptor (LDLr) is located on the adrenal cells to facilitate

Answer 23

endocytosis of cholesterol

Question 24

Adrenal androgens, DHEA and androstenedione, are produced in the fasciculata/reticularis and have

Answer 24

weak androgenic activity

Question 25

Zona fasciculata/reticularis are under control of

Answer 25

hypothalamic-pituitary axis

Question 26

CRH is released by

Answer 26

paraventricular nuclei

Question 27

CRH acts on corticotrophs via adenylyl cyclase/cAMP to

Answer 27

stimulate release of ACTH

Question 28

Excess cortisol will _______ ACTH levels

Answer 28

decrease

Question 29

Cortisol deficiency will _______ ACTH levels

Answer 29

increase

Question 30

Chronic release of ACTH will have a ______ effect on the adrenal celsl and can induce hyperplasia

Answer 30

trophic

Question 31

ZG does not produce

Answer 31

glucocorticoids

Question 32

Why does ZG not produce glucocorticoids?

Answer 32

- Aldosterone synthase converts corticosterone to aldosterone - It lacks 17,alpha-hydrozylase and is unable to convert progesterone to cortisol

Question 33

If there is a block at 21,β-hydroxylase or above, then

Answer 33

no mineralocorticoids will be produced

Question 34

What factors can stimulate ACTH secretion?

Answer 34

- Stress, hypoglycemia, trauma, some drugs

Question 35

What factors can inhibit ACTH secretion?

Answer 35

Somatostain, some drugs, increased blood cortisol levels

Question 36

Cortisol will induce the synthesis of _______ which is an inhibitor of phospholipase A2

Answer 36

lipocortin

Question 37

Cortisol inhibits the production of ______ and the proliferation of T lymphocytes

Answer 37

IL-2

Question 38

Cortisol inhibits the release of ______ and _______ from mast cell and platelets

Answer 38

histamine and serotonin

Question 39

What syndrome is the hypersecretion of cortisol?

Answer 39

Cushing's syndrome

Question 40

Cushing's syndrome can be due to

Answer 40

chronic excess of glucocorticoids or from hypersecretion of cortisol from adrenal such as tumor

Question 41

Excess cortisol can cause

Answer 41

hyperglycemia, increase in protein/lipid catabolsim, central obesity, poor wound healing, osteoporosis, hypertension

Question 42

How is cushings treated?

Answer 42

Ketoconazole or metyrapone to block synthesis of glucocorticoids/adrenal androgens

Question 43

Addisons is the loss of

Answer 43

adrenocorticol hormones

Question 44

Addisons is commonly caused by

Answer 44

Auto immune destruction of adrenal cortex

Question 45

Addisons is also known as

Answer 45

primary adrenocortical insufficiency

Question 46

In addisons, there is a decrease in

Answer 46

all adrenocortical hormones

Question 47

Loss of adrenocortical hormones will cause

Answer 47

hypoglycemia, hypotension, hyperkalemia, metabolic acidosis, weight loss

Question 48

Why will pt with Addisons have hyperpigmentation?

Answer 48

Increase alpha MSH as a result of excess ACTH levels

Question 49

ACTH, AngII, and increased extracellular potassium will all increase the release of

Answer 49

aldosterone

Question 50

Aldosterone can be stimulated by

Answer 50

ACTH, low BP/volume through activation of RAAS and high plasma K

Question 51

High extracellular K will act on adrenal cells to depolarize the cell membrane, which will do what?

Answer 51

Open VGCCs

Question 52

Increases in intracellular calcium will activate

Answer 52

aldosterone synthase

Question 53

Degradation of aldosterone occurs through

Answer 53

glucoronidation in liver

Question 54

Once sodium and water are reabsorbed, this will increase arterial blood pressure. which will promote

Answer 54

pressure diuresis (loss of Na and water)

Question 55

What is aldosterone escape?

Answer 55

The return of sodium and water back to normal once pressure diuresis is promoted?

Question 56

What is Conn Syndrome?

Answer 56

Primary aldosteronism. Results from hypersecretion of aldosterone in absence of known stimulus

Question 57

What is secondary aldosteronism?

Answer 57

Increased aldosterone secretion as a result of known stimulus (Increased AngII)

Question 58

Slight expansion of volume will occur along with

Answer 58

sodium reabsorption, K+ secretion, and H+ secretion

Question 59

Conn syndrome patient will be

Answer 59

hypertensive and arterial pH (metabolic alkalosis)

Question 60

In Conn syndrome, what will happen to renin levels?

Answer 60

Will be decreased due to increase in ECF volume and increased renal perfusion pressure

Question 61

What is treatment for Conn syndrome?

Answer 61

Administration of an aldosterone receptor antagonist followed by surgical removal of tumor

Question 62

Adrenal adenoma can produce either

Answer 62

Cushing's syndrome or Conn Syndrome