Brain chemistry 2 + knowledge clips gut

Question 1

Where is melatonin produced?

Answer 1

Pineal gland
Know where it is located (p14)

Question 2

Where is histamine produced?

Answer 2

Mast cells
Tuberomamillary nucleus (posterior hypothalamus)

Question 3

Where is serotonin (5-HT: 5-hydroxytryptamine) produced in the brain?

Answer 3

Raphe nuclei (dorsal, medial, caudal) (achterkant pons)

Question 4

Where is norephinephrine/noradrenaline produced?

Answer 4

Locus coeruleus (onder raphe nuclei, achterkant pons, maar iets lager

Question 5

What do the substantia nigra do? Pinpoint them p.15

Answer 5

black dots of neurons that make dopamin.
Recognize substantia nigra!

Question 6

What are the four dopamine pathways? (and their nuclei)

Answer 6

• Nigrostatial (substantia nigra)
• Tuberoinfundibular (arcuate nucleus)
• Mesolimbic (ventral tegmental area: VTA)
• Mesocortical (VTA)
  p.15

Question 7

Dopamine can be metabolized into…. (3)

Answer 7

• DOPAC
• HVA
• noradrenaline -> (can in turn be metabolized into adrenalin)

Question 8

What is an important enzyme that helps to convert/metabolize dopamine into other substances/neurotransmitters? (metabolites, noradrenaline, adrenaline, serotonin)

Answer 8

MAO = monoamine oxidase

Question 9

What is the serotonin theory? What is a limitation?

Answer 9

chemical imbalance: depletion 5-HT in depressed patients.
Limitation: not all individuals respons to 5-HT agonists or SSRI

Question 10

What do SSRI do?

Answer 10

Selective serotonin reuptake inhibitors

SSRI block the serotonin reuptake

Question 11

What are current treatments for depression?

Answer 11

-SSRI
- 5-HT receptor agonists
- TCA
- MAO inhibitors
- supplements (5-HTP)

Question 12

Half-life of antidepressants are quite long. What can be the risk of taking, for instance, 5-HTP?

Answer 12

If 5-HTP is taken together with something like an SSRI, it can cause the serotonin syndrome -> seizures -> die

Question 13

What is the link between aggression and serotonin?

Answer 13

Too low serotonin = too much aggression link
However, lower levels of serotonin (5-HT) are perhaps aspecific because they are also related with migrain, depression, OCD, anxiety, gambling

Question 14

What does alcohol do to serotonin levels?

Answer 14

Alcohol lowers tryptophan, which is a precursor for serotonin synthesis and thus also lowers 5-HT synthesis (-20%!)

Question 15

Alcohol leads to aggression in people that….

Answer 15

already have low levels serotonin

Question 16

Alcohol can bind to GABA, leading to a ….. effect

Answer 16

sedating

Question 17

What happens during Parkinson’s disease in the brain? What part is most effected?

Answer 17

Accumulation of alfa-synuclein depositions, which causes Lewy bodies in neurons in the brain. Substantia nigra mostly affected.
-> disrupted connection of substantia nigra with basal ganglia which regulate movement: leading to tremor etc

Question 18

What happens during AD?

Answer 18

• Proteinopathy (accumulation of amyloid plaques and neurofibrillary tangles)
• Leads to massive death of neurons.
• Cholinergic disturbances: n. basalis of Meynert = cognitive dysfunction

Question 19

PD: not only dopamine disturbances, also …. disturbances

Answer 19

norepinephrine, serotonin

Question 20

AD: what types of neurotransmitters have disturbances?

Answer 20

Dopamine,serotonine, norepinephrine disturbances

Question 21

What happens to the locus coeruleus (nucleus in pons of brainstem) in AD?

Answer 21

Completely gone in AD: vasoconstriction

Question 22

Which statements are true:

1. Agressive behaviour is linked to a reduced serotonergic neurotransmission
2. Current pharmacological treatments for depression solely consists of SSRI’s
3. Alcohol intake leads to increased levels of serum tryptophan
4. AD and PD are characterized by abundant serotonin, dopamine and norepinephrine losses in the brain (and periphery)

Answer 22

1, 4 are true

Question 23

Phenylalanine, tryptophan, histidine: essential or non-essential AA?

Answer 23

essential

Question 24

What are some GABA-rich foods?

Answer 24

tomatoes, potatoes

Question 25

What is a food high in acetylcholine?

Answer 25

aubergine

Question 26

Most amino acid rich foods are …. from origin

Answer 26

animal-based

Question 27

What 5 factors determine whether certain amino acids/etc reach the brain?

Answer 27

1. transporter proteins across the BBB
2. Influence from non-neuronal tissues (GI tract, peripheral enzymes)
3. Cooking methods, fresh vs processed, baked,..
4. seasonal, geographical, species-aspects
   (plant species, soul, nourishmnet,..)
5. micronutrient & trace element status

Question 28

What are the steps in making serotonin?

Answer 28

Tryptophan -> 5-HTP -> Serotonin

Question 29

What are the steps in making dopamine & noradrelane?

Answer 29

Tyrosine -> L-dopa -> dopamine -> noradrenaline

Question 30

Where is epinephrine/adrenalin produced?

Answer 30

• Central adrenergic cell bodies
  ● Ventral/dorsal group -> medulla oblongata (onder pons)
  ● Catabolized out of norepinephrine (!)
  ● Axonal projections ≈ noradrenergic systems

Question 31

Where is dopamine produced?

Answer 31

● Substantia nigra
● Tuberoinfundibular pathway
● Mesolimbic pathway
● Mesocortical pathway

Question 32

Where is acetylcholine produced?

Answer 32

• nucleus basalis of meynert (see image p. 16)
• three other nuclei

Question 33

p.16:
1. Where does the cholinergic pathway start?
2. Where does the serotonergic pathway start?
3. Where does the Histaminergic pathway start?
4. Where does the Dopaminergic pathway start?
5. Where does the Noradrenergic pathway start?

Answer 33

1. Cholinergic nucleus at basalis of meynert
2. Serotonergic nucleus at Raphe nuclei
3. Histaminergic nucleus at tuberomammilary nucleus
4. Dopaminergic nuclei, substantia nigra, Ventral tegmental area (VTA)
5. Noradrenergic nucleus at locus coeruleus