Neurotransmitters and Their Precursors Flashcards
Phenylalanine function/defect
Phenylketonuria missing phenylalanine hydroxylase
Phenylalanine reactions
Phe -> Tyr
What is NutraSweet?
- D/L phenylalanine + aspartate
- AKA: Aspartame
What does tyrosine convert into?
L dopa
What does L dopa convert into?
Dopamine
What does dopamine convert into?
Norepinephrine
What does norepinephrine convert into?
Epinephrine
Regarding pigmentation, what does tyrosine convert into?
Melanin
What enzyme converts tyrosine into melanin?
Tyrosinase
Regarding thyroid hormones, what does tyrosine convert into?
Thyroxine (T4 inactive)
Triiodothyronine (T3 active)
What does T4/T3 control?
Metabolism by making bigger and more mitochondria
What can tryptophan be converted into?
- Serotonin
- Melatonin
- Niacin
Serotonin reaction
Trp -> 5OHTrp ->5HTP (5 hydroxytryptamine)
High levels of tryptophan
- Panic
- Diarrhea
Low levels of tryptophan
- Worry
- Constipation
Melatonin reaction
Low light in pineal gland -> melatonin
Histidine function
H1 histamine receptor:
- Capillary (vasodilator)
- Hypothalamus (releases anterior pituitary hormone)
H2 histamine receptor:
- Parietal cells (stomach)
- Releases stomach cells
Histidine reactions
Histidine -> histamine
Most important excitatory NT in the CNS
Glutamate
Glutamate “gatekeeper”
Magnesium
What does glutamate bind to?
NMDA receptor
Most important inhibitory NT in the CNS
GABA
Low levels of glutamate
Depression
Inhibitory NT in skeletal muscle interneuron
Glycine
AA responsible for vasodilation
Arginine
Arginine reaction
- Arginine -> Citrulline
- Makes nitric oxide
What does the metabolism of AAs require?
Vitamin B6
