Catecholamines and Serotonin

Question 1

1. The urinary metabolite measured as an indicator of norepinephrine synthesis is:
   a. dopamine.
   b. homovanillic acid (HVA).
   c. serotonin.
   d. vanillylmandelic acid (VMA).

Answer 1

d. vanillylmandelic acid (VMA).

Question 2

2. False-positive elevations of 5-hydroxyindoleacetic acid
   (5-HIAA) in urine can occur if:

a. an individual is a chronic alcoholic.
b. a patient is receiving aspirin therapy.
c. an individual has recently eaten fruit, such as bananas, kiwis, and plums.
d. a patient is currently using tricyclic antidepressants

Answer 2

c. an individual has recently eaten fruit, such as bananas, kiwis, and plums.

Question 3

3. The two urine metabolites that are most widely used for
   the diagnosis of neuroblastoma are:
   a. HVA and VMA.
   b. VMA and 5-HIAA.
   c. HVA and 5-HIAA.
   d. dopamine and epinephrine

Answer 3

a. HVA and VMA.

Question 4

4. Midgut neuroendocrine tumors release which of the following substances in a large quantity when compared
   with tumors derived from other developmental gut components?

a. 5-hydroxytryptophan
b. Serotonin
c. Epinephrine
d. Dopamine

Answer 4

b. Serotonin

Question 5

5. The method most frequently used for measuring 5-HIAA
   in urine to detect serotonin production is:
   a. nephelometry.
   b. liquid chromatography with UV detection.
   c. liquid chromatography with electrochemical, fluorimetric or mass spectrometric detection.
   d. ion exchange chromatography

Answer 5

c. liquid chromatography with electrochemical, fluorimetric or mass spectrometric detection.

Question 6

6. The recommended analytes for diagnosis of pheochromocytoma are:
   a. urinary VMA and HVA.
   b. plasma or urinary metanephrines.
   c. urinary or plasma catecholamines.
   d. urinary 5-HIAA and HVA

Answer 6

b. plasma or urinary metanephrines.

Question 7

7. A catecholamine-producing tumor derived from the
   chromaffin cells of the adrenal medulla is referred to as a:
   a. neuroblastoma.
   b. pheochromocytoma.
   c. paraganglioma.
   d. gastroenteropancreatic neuroendocrine tumor

Answer 7

b. pheochromocytoma

Question 8

8. More than 95% of the serotonin in the body is produced
   within the gastrointestinal tract.
   a. True.
   b. False

Answer 8

a. True.

Question 9

9. Chromaffin cells are located in the ___ and are responsible for synthesis of___:
   a. kidney; renin.
   b. brain; dopamine.
   c. adrenal gland; epinephrine.
   d. gut; serotonin.

Answer 9

c. adrenal gland; epinephrine.

Question 10

10. Epinephrine is also called:
    a. noradrenaline.
    b. adrenaline.
    c. metanephrine.
    d. serotonin.

Answer 10

b. adrenaline.