Exam 4; Glucocorticoids

Question 1

The synthesis of steroids is essentially via which enzymes

Answer 1

P450s

Question 2

What is the mechanism of action of steroids

Answer 2

enter the target cell and bind to a cytoplasmic receptor

Question 3

The steroid dimerizes, then binds to a response element in the DNA, causing what to occur

Answer 3

either enhance gene transcription or suppress gene transcription

Question 4

Regarding glucocorticouds, this is induced

Answer 4

lipocortin 1

Question 5

What is the function of lipocortin 1

Answer 5

it is an extremely important regulator of the immune system; inhibits phospholipase A2 → decrease in arachniodonic acid → inhibiting the synthesis of prostaglandins and leukotrienes

Question 6

Lipocortin inhibits the synthesis of may what

Answer 6

cytokines, leading to a profound suppression of the immune system

Question 7

What is the immunosuppressive potency, relative mineralcorticoid, and duration of cortisone and hydrocortisone

Answer 7

immunosuppressive potency; 1
relative mineralcorticoid; 1
duration 8-12 hours

Question 8

What is the immunosuppressive potency, relative mineralcorticoid, and duration of prednisone, triamcinolone, and predinisolone

Answer 8

immunosuppressive potency; 4
relative mineralcorticoid; 0.25
duration; 18-36 hours

Question 9

What is the immunosuppressive potency, relative mineralcorticoid, and duration of dexamethasone and betamethasone

Answer 9

immunosuppressive potency; 25
relative mineralcorticoid; <0.01
duration; 36-54 hours

Question 10

What type of drugs are the GCs

Answer 10

pro-drugs; must be metabolized by P450

Question 11

Why are GCs not effective when used topically

Answer 11

topical use can lead to systemic effects

Question 12

What can topical use of GCs be affected by

Answer 12

Dose
Duration of exposure
Potency
Size of area covered
Occlusive dressings
Skin damage
Thickness of the skin

Question 13

What are the side effects of a deficiency of cortisol production

Answer 13

Weight loss
low BP
muscle weakness
Addison’s disease

Question 14

What are the side effects of an excess production of cortisol (Cushing’s)

Answer 14

adrenal suppression; body is no longer making its of GCs; relying on exogenous GCs, which some from no where; leading to Addison’s like symptoms

Question 15

What are the metabolic effects of GCs

Answer 15

Increased liver gluconeogenesis
Decreased glucose uptake by muscle cells
Increased protein breakdown
Decreased protein synthesis
Affects lipolysis; fat redistribution