Endocrine: 15.10: Adrenal Cortex

Question 1

What is Cushing syndrome?

Answer 1

excess cortisol

Question 2

Pregnenolone is converted into _____ via 21-hydroxylase AND 11-hydroxylase.

Answer 2

cortisol

Question 3

What is made in the zona reticularis?

Answer 3

sex steroids

Question 4

What are the s/s of chronic adrenal insufficiency?

Answer 4

• lack of cortisol:
  
  • hypotension
  • increased ACTH –> hyperpigmentation (esp of oral mucosa)
  • vomiting, diarrhea
• lack of aldosterone:
  
  • hyponatremia
  • hypovolemia
  • hyperkalemia

Question 5

The adrenal cortex secretes hormones derived from _____.

Answer 5

cholesterol

Question 6

Why do pts with Cushings get HTN?

Answer 6

cortisol upregulates alpha-1 receptors on arterioles –> increased effects of NE

Question 7

Pregnenolone is converted into cortisol via _____.

Answer 7

• 21-hydroxylase AND
• 11-hydroxylase

Question 8

Pregnenolone is converted into ______ via 21-hydroxylase.

Answer 8

mineralocorticoids and cortisol

Question 9

How does cortisol cause immunosuppression?

Answer 9

• inhibits phospholipase A2
• inhibits IL-2
• inhibits mast cell histamine release

Question 10

What happens in Waterhouse-Friderichsen syndrome?

Answer 10

DIC –> bilateral necrosis of adrenal glands –> acute lack of cortisol –> massive hypotension

Question 11

What is made in the zona fasciculata?

Answer 11

cortisol (glucocorticoids)

Question 12

ACTH is derived from _____.

Answer 12

POMC

Question 13

Name a mineralocorticoid.

Answer 13

Aldosterone

Question 14

Cortisol ____ blood sugar by breaking down muscle.

Answer 14

increases

Question 15

What are the lab findings in hyperaldosteronism?

Answer 15

• hypernatremia
• hypokalemia
• metabolic alkalosis
• HTN

Question 16

Aldosterone causes ____ Na+ and _____ K+.

Answer 16

• increased Na+
• decreased K+

Question 17

Pregnenolone is converted into cortisol via _____.

Answer 17

21-hydroxylase

Question 18

How is Cushings diagnosed?

Answer 18

• increased 24 hour urinary cortisol
• high dose dexamethasone test

Question 19

What happens if phospholipase A2 is inhibited?

Answer 19

no arachidonic acid metabolites form –> no inflammation

Question 20

What is 17-hydroxylase important for?

Answer 20

pregnenolone conversion into cortisol and sex steroid hormones

Question 21

Acute adrenal insuffienciency is usually caused by ______.

Answer 21

Waterhouse-Friderichsen syndrome

Question 22

Why is cortisol essential for life?

Answer 22

it regulates blood vessel tone

Question 23

In which hydroxylase deficiency is cortisol not produced?

Answer 23

ALL of them! (17, 11, 21)

Question 24

What will the results of a high dose dexamethasone test be in Cushings from a pituitary adenoma?

Answer 24

suppression

Question 25

What cancer loves to metastasize to the adrenals?

Answer 25

lung cancer

Question 26

What will the results of a high dose dexamethasone test be in Cushings from an ectopic ACTH producing cancer?

Answer 26

failure of suppression

Question 27

Why are abdominal striae seen in Cushings?

Answer 27

cortisol impairs collagen synthesis --\> BVs rupture easily

Question 28

What are the s/s of 21-hydroxylase deficiency in a female?

Answer 28

* clitoral enlargement * hypotension * bilateral adrenal hyperplasia * hyponatremia * hyperkalemia * dehydration

Question 29

Dx? * adrenal gland looks like a sack of blood

Answer 29

Waterhouse-Friderichsen syndrome

Question 30

Excess insulin causes _____ storage of fat.

Answer 30

increased

Question 31

What bacteria causes Waterhouse-Friderichsen syndrome?

Answer 31

N. meningiditis

Question 32

What happens when IL-2 is inhibited?

Answer 32

T-cells aren't stimulated to grow

Question 33

What are the s/s of 21-hydroxylase deficiency in a male?

Answer 33

* precocious puberty * hypotension * bilateral adrenal * hyperplasia * hyponatremia * hyperkalemia * dehydration

Question 34

Name the 2 catecholamines.

Answer 34

1. Epi 2. NE

Question 35

Pregnenolone is converted into mineralocorticoids via \_\_\_\_\_.

Answer 35

21-hydroxylase

Question 36

Name the most common tumor to secrete ACTH.

Answer 36

small cell carcinoma of the lung

Question 37

If there is a deficiency of 21-hydroxylase, there will be decreased _____ and increased \_\_\_\_\_.

Answer 37

* decreased mineralocorticoids and cortisol * increased sex steroid hormones