Specialized Amino Acid Products

Question 1

Parkinson’s Disease

Answer 1

loss of dopamine producing cells in basal ganglia

movement disorders

• spasticity
• tremors
• loss of memory
• mood disturbances
• postural instability

administration of L-DOPA
(converted to Dopamine in brain)

administered with Dopa decarboxylase inhibitors to prevent rapid degradation in neuronal cells

Question 2

Pheochromocytoma

Answer 2

adrenal medulla tumor (overproduction of catecholamines)

-headache, sweating, tachycardia, hypersensitive, hypertension

24 hour urinary measurment during symptom episode

NE and E degraded by monoamine oxidase (MAO) and catechol O-methyl transferase (COMT) form VMA (vanilly mandelic acid)

Question 3

Carcinoid Cancer (Serotonin overproduction)

Answer 3

increased 5-HIAA excretion in urine

serotonin metabolized to 5-hydroxyindole acetic acid (5-HIAA) by monoamine oxidase (MOA)

• diarrhea, flushing, sweating, bronchospasm
• tumor of serotonin producing cells of GIT (APUD cells)

Question 4

Tetrahydrobiopterin Deficiency

Answer 4

BH4/dihydrobiopterin reductase deficiency

• tyrosine synthesis (Phe hydroxylase)
• catecholamine synthesis (Tyr hydroxylase)
• serotoinin synthesis (Trp hydroxylase)
• hyperphenylalaninemia
• decreased synthesis of NT (catecholamines, serotonin, delayed mental develpment, seizures)

addition of dietary tetrahydrobiopterin and provision precursors of NT in diet

dietary Phe restriciton

Question 5

Albinism

Answer 5

deficiency- Tyrosinase enzyme
(deficient conversion of tyrosine to Melanin)

severe form- occulocutaneous albininism

lower visual acuity
photophobia
light colored skin and hair
increased risk of skin damage on exposure to sunlight
increased risk of skin cancer