Lecture 18 - Adrenal Glands I

Question 1

From superficial to deep, what are the layers of the adrenal gland?

Answer 1

1) Capsule
2) Zona glomerulosa
3) Zona fasciculata
4) Zona reticulata
5) Medulla

Question 2

What hormone does the zona glomerulosa respond to?

Answer 2

Angiotensin II

Question 3

What hormones do the zona reticulata and fasciculata respond to?

Answer 3

ACTH and CRH

Question 4

Which arteries supply the adrenal glands?

Answer 4

Suprarenal arteries

Question 5

Which hormones do the adrenal medulla produce?

Answer 5

epinephrine and norepinephrine

Question 6

What type of cells are in the adrenal medulla and from where do they come from?

Answer 6

1) chromaffin cells

2) modified post-ganglionic sympathetic fibers

Question 7

What innervates the adrenal medulla?

Answer 7

preganglionic sympathetic

Question 8

Where is CRH made in the hypothalamus?

Answer 8

paraventricular nucleus

Question 9

Which second messenger does CRH work through?

Answer 9

cAMP

Question 10

Which corticosteroids are activated by CRH?

Answer 10

all of them

Question 11

Which corticosteroids exert negative feedback on the hypothalamus?

Answer 11

cortisol

Question 12

Which corticosteroids exert negative feedback on the anterior pituitary?

Answer 12

cortisol

Question 13

What type of release does ACTH follow?

Answer 13

diurnal and pulsatile

Question 14

Which protein is ACTH derived from?

Answer 14

POMC

Question 15

When ACTH is chronically elevated, what morphological change to the adrenal gland happens?

Answer 15

hypertrophy of adrenal cortex

Question 16

Hypertrophy of the adrenal cortex leads to what biochemical change?

Answer 16

Increase in LDL-Rs and increased transcription of steroid hormone synthesis enzymes

Question 17

What is a side effect of chronically elevated ACTH?

Answer 17

increased melanin synthesis due to alpha-MSH

Question 18

What is the purpose of StAR protein?

Answer 18

Shuttles cholesterol from the cytosol to the mitochondria

Question 19

Adrenocortical cells have which type of receptor?

Answer 19

lipoprotein receptors

Question 20

Where does most cholesterol for the synthesis for steroid hormones come from?

Answer 20

circulating cholesterol

Question 21

What is the first metabolite for steroid hormone synthesis that cholesterol turns into?

Answer 21

pregnenolone

Question 22

What are the two main physiologic consequences of aldosterone release?

Answer 22

Increased sodium resorption and increased potassium secretion

Question 23

Aldosterone also controls fluid balance, how?

Answer 23

Through sodium resorption, leading to water retention

Question 24

What is the major physiologic regulator of aldosterone?

Answer 24

angiotensin II

Question 25

Other than Ang II, what else stimulates aldosterone?

Answer 25

hyperkalemia

Question 26

What stimulates angiotensin II production?

Answer 26

Decrease in blood volume

Question 27

What second messengers do angiotensin II work through? What about hyperkalemia?

Answer 27

IP3/DAG/Ca | Hyperkalemia works through calcium

Question 28

What are the two main functions of aldosterone?

Answer 28

1) maintain blood volume | 2) regulate hydrogen and potassium secretion

Question 29

Which cells are acted upon by aldosterone?

Answer 29

principal cells of the distal tubule and collecting duct

Question 30

The hydrogen-potassium exchanger functions mostly where?

Answer 30

collecting duct

Question 31

What controls the rate of aldosterone production?

Answer 31

renin release from the kidney

Question 32

What is primary hyperaldosteronism also called?

Answer 32

Conn's syndrome

Question 33

What physiological symptoms is NOT present in hyperaldosteronism that you would expect to be present? Why?

Answer 33

EDEMA, because of an "aldosterone escape mechanism"

Question 34

What is the difference between primary and secondary hyperaldosteronism?

Answer 34

Primary: high aldosterone, low renin Secondary: high aldosterone, high renin

Question 35

What is the cause of primary hyperaldosteronism? Secondary hyperaldosteronism?

Answer 35

Primary: adrenal adenoma, idiopathic hyperplasia Secondary: renovascular HTN, juxtaglomerular cell tumor

Question 36

What are the four main symptoms of hyperaldosteronism?

Answer 36

1) hypertension 2) hypokalemia 3) alkalosis 4) decreased renin secretion

Question 37

What causes the hypertension in hyperaldosteronism? How about the hypokalemia?

Answer 37

HTN: increase in ECF volume due to increase sodium reabsorption Hypokalemia: increased potassium secretion in urine

Question 38

What are the three main symptoms of hypoaldosteronism?

Answer 38

1) hyperkalemia 2) metabolic acidosis 3) hyponatremia