Enzymes

Question 1

What does 11-ß-Hydroxylase do?

Answer 1

11-Deoxycorticosterone –> Corticosterone

11-Deoxycortisol –> Cortisol

Question 2

What does 11-ß-Dehydrogenase do?

Answer 2

Cortisol –> Cortisone

Question 3

What does 17-alpha-Hydroxylase do?

Answer 3

Pregnenolone –> 17-alpha-Hydroxypregnenolone

Progesterone –> 17-alpha-Hydroxyprogesterone

Question 4

What does 21-alpha-Hydroxylase do?

Answer 4

Progesterone –> 11-Deoxycorticosterone

17-alpha-Hydroxyprogesterone –> 11-Deoxycortisol

Question 5

What does COMT do?

Answer 5

Epi –> Metanephrin

Nepi –> Normetanephrin

Question 6

What does PMNT do?

Answer 6

Nepi –> Epi

Question 7

What does Phospholipase A2 do?

Answer 7

Liberates Arachidonic Acid for synthesis of prostaglandins and leukotrienes (inhibited by lipocortin which is released by glucocorticoids)

Question 8

What does 24-Hydroxylase do?

Answer 8

25-OH-Cholecalciferol –> 24, 25-OH-Cholecalciferol (in kidney)

Question 9

What does 1-alpha-Hydroxylase (CYP1-alpha) do?

Answer 9

25-OH-Cholecalciferol –> 1, 25-Di-OH-Cholecalciferol (in kidney)

Question 10

What does 25-Hydroxylase do?

Answer 10

Cholecalciferol (D3) –> 25-OH-Cholecalciferol (in liver)

Question 11

What does 5’-Iodinase/Deiodinase types 1 and 2 do?

Answer 11

T4 –> T3 at target tissue

Question 12

What does Thyroid Peroxidase do?

Answer 12

Iodide (I-) –> Iodine (I2)
I2 + TG –> MIT/DIT
DIT + DIT –> T4
DIT + MIT –> T3

Question 13

What does Thyroid Deiodinase do?

Answer 13

MIT/DIT –> Tyr and I-