Steroids

Question 1

What effects do glucocorticoids have?

Answer 1

Primary effects on carbohydrate and protein metabolism

Anti-inflammatory effects

Question 2

Aldosterone, Cortisol and Estradiol are synthesized from what?

Answer 2

Cholesterol

Question 3

Prednisolone, Dexamethasone, Fludrocortisone and Hydrocortisone (Cortisol) are in what class of drugs?

Answer 3

Synthetic corticosteroids

Question 4

Which synthetic corticosteroids are salt-retaining?

Answer 4

Mineralocorticoids (Fludrocortisone, Desoxycorticosterone acetate)

Question 5

Which mineralocorticoid is choice for replacement therapy?

Answer 5

Fludrocortisone

Question 6

Cortisol synthesis is stimulated by what?

Answer 6

ACTH

Question 7

Aldosterone synthesis is stimulated by what?

Answer 7

Angiotensin II and K+

Question 8

Where are cortisol and aldosterone synthesized?

Answer 8

Adrenal cortex

Question 9

Where does glucocorticoid synthesis regulation occur?

Answer 9

Hypothalamic-Pituitary-Adrenal Axis

Question 10

What controls ACTH release?

Answer 10

CRH (Corticotropin Releasing Hormone) released from hypothalamic neurons

Question 11

Where is ACTH released from?

Answer 11

Anterior pituitary

Question 12

What does ACTH simulate?

Answer 12

Cortisol synthesis and release

Question 13

How is glucocorticoid synthesis regulated?

Answer 13

1. episodic secretion and circadian rhythm of ACTH
2. stress responsiveness of the HPA axis
3. feedback inhibition by cortisol of ACTH secretion

Question 14

What is the mechanism of action of ACTH on cortisol secreting cells in the adrenal cortex?

Answer 14

1. ACTH binds to receptor, adenylyl cyclase activated via Gs
2. Increased cAMP activates PKA
3. PKA phosphorylates cholesteryl ester hydrolase
4. more free cholesterol formed and converted to pregnenolone in mitochondria
5. products are shuttled between mitochondria and smooth endoplastic reticulum

Question 15

What are the physiological actions of glucocorticoids?

Answer 15

Carbohydrate/Protein/Lipid metabolism
Maintain blood glucose levels during fasting
Calcium homeostasis
Cardiovascular system: HTN with prolonged high levels
Skeletal muscle wasting with prolonged high levels
CNS: excss or insufficiency
Endocrine system: decrease of secretion of growth hormone, increase in epinephrine synthesis, decrease in major hormone binding proteins

Question 16

Do steroids prevent or suppress disease processes?

Answer 16

No, they suppress inflammation

Question 17

What mobilized amino acid in response to prolonged fast?

Answer 17

Cortisol

Question 18

A specific nucleotide sequence that is recognized by a steroid hormone receptor-hormone complex describes what?

Answer 18

Glucocorticoid response element (GRE)

Question 19

How is inflammation inhibited via the glucocorticoid receptor?

Answer 19

Increased Annexin A1 (lipocortin 1) production
Decreased Cyclooxygenase 2 (COX-2) synthesis, decreased prostaglandin and leukotriene production
Decreased TNF-a synthesis

Anti-inflammatory effects and immunosuppressive effects of glucocorticoids are linked

Question 20

What produces TNF?

Answer 20

Macrophages, lymphocytes, natural killer cells

Question 21

What is the most severe adverse effect of glucocorticoids?

Answer 21

Acute adrenal insufficiency

Question 22

What is a side effects of glucocorticoids seen in children?

Answer 22

Growth suppression