5) Neurotransmitters Flashcards Preview

Mood Disorders > 5) Neurotransmitters > Flashcards

Flashcards in 5) Neurotransmitters Deck (21):
1

Describe the features of a neuron:

Dendrites at receiving end
Soma (cell body)
Axon +/- myelin sheath
Terminal buttons

2

What are the two main neurotransmitters involved in depressive disorders?

Noradrenaline
Serotonin

3

What other neurotransmitter are involved in psychiatric conditions?

Dopamine
GABA
ACh
Glutamate

4

What are the functions of noradrenaline in the brain?

Mood
Role in behaviour (arousal and attention)
Implicated in memory functions

5

Where is noradrenaline made in the brainstem?

Locus coeruleus

6

What role do alpha receptors play in the brain?

Arousal and mood

7

What enzymes break down noradrenaline?

Monoamine oxidase
COMT

8

Describe the synthesis of noradrenaline:

Tyrosine -> DOPA -> Dopamine -> noradrenaline (-> adrenaline)

9

What evidence is there for noradrenaline being implicated in depression?

AMPT inhibits formation of NA and cause depressive symptoms
Antidepressants block reuptake of NA
Reserpine depletes nerve ends of NA (causes depressive symptoms)

10

What is the role of serotonin in the brain?

Sleep
Impulse control
Appetite
Mood

11

Where in the brainstem is serotonin produced?

Raphe nuclei

12

What is serotonin synthesised from?

Tryptophan

13

What can serotonin go on to form?

Melatonin (control of sleep)

14

What evidence is there for serotonin being implicated in depression?

Metabolite of serotonin in CSF is depleted in depression
Tryptophan depletion causes depression
PET and SPET studies
Antidepressants (SSRIs)

15

What disorders are changes to dopamine associated with?

Parkinson's disease
Schizophrenia

16

What effect does dopamine have?

Feelings of pleasure
Drive

17

What evidence is there for dopamine being implicated in depression?

HVA (metabolite of dopamine) low in depressed
ECT affects dopamine system
40% of those with Parkinson's have depression

18

Describe some neurotransmitter changes in mania:

NA increased
Dopamine agonists cause manic symptoms

19

How does lithium act as a mood stabiliser?

Positive effect on BDNF transcription
Positive effect on serotonin production

20

How do GABAa receptors cause an effect?

Chloride ion channels (inhibitory)

21

How do GABAb receptors cause an effect?

Secondary messengers