Parkinson's Disease and Schizophrenia

Question 1

Name the 3 monoamine neurotransmitters.

Answer 1

Dopamine
Noradrenalin
5-HT/Serotonin

Question 2

What are the two catecholamines?

Answer 2

Dopamine and noradrenalin

Question 3

What is the indolamine?

Answer 3

5-HT/Serotonin

Question 4

Is dopamine ionotropic or metabotropic?

Answer 4

Metabotropic

Question 5

Where are dopamine cell bodies located?

Answer 5

Substantia nigra.

Question 6

Which part of the brain is the substantia nigra in?

Answer 6

Midbrain/mesencephalon

Question 7

What colour are the dopamine cell bodies?

Answer 7

Black

Question 8

Where do the dopamine cell bodies project dopamine to?

Answer 8

The striatum

Question 9

What is the largest component of the basal ganglia?

Answer 9

The striatum

Question 10

What is the basal ganglia?

Answer 10

Collections of subcortical nuclei deep in the cerebral hemisphere.

Question 11

What are the two parts of the striatum?

Answer 11

Dorsal and ventral

Question 12

What does the dorsal striatum contain?

Answer 12

The caudate nucleus and putamen

Question 13

What does the ventral striatum contain?

Answer 13

Nucleus accumbens

Question 14

What is the caudate nucleus responsible for?

Answer 14

Learning and inhibition

Question 15

What is the putamen responsible for?

Answer 15

Motor skills and motor learning

Question 16

What are the nucleus accumbens responsible for?

Answer 16

Reward, motivation, addiction and fear.

Question 17

Which part of the brain is the basal ganglia in?

Answer 17

The forebrain/telencephalon

Question 18

What does the nigrostriatal pathway do?

Answer 18

Connects dopamine neurons in the substantia nigra (midbrain) to the caudate nucleus and putamen -> dorsal striatum -> basal ganglia.

Also contains axons which allow dopamine neurons to travel from the ventral tegmental area to the nucleus accumbens -ventral striatum.

Question 19

What is the MFB and what does it do?

Answer 19

Medial forebrain bundle. Takes dopamine neurons from the substantia nigra to the striatum

Question 20

What does cardinal mean?

Answer 20

Most significant/important.

Question 21

What are the three cardinal symptoms of Parkinson’s Disease?

Answer 21

• Rigidity
• Bradykinesia (slowness of movement)
• Tremors

Question 22

Why does Parkinson’s disease occur?

Answer 22

Dopamine neurons in the substantia nigra degenerate.

Question 23

What is it that causes the cardinal symptoms of Parkinson’s disease?

Answer 23

The loss of dopamine in the striatum.

Question 24

What percentage of dopamine neurons have to be lost before symptoms of Parkinson’s start to appear?

Answer 24

80%

Question 25

What is the main treatment of Parkinson's disease?

Answer 25

Dopamine replacement therapy.

Question 26

Describe the sequence of dopamine synthesis.

Answer 26

- Tyrosine converted to levodopa with tyrosine hydroxylase. | - Levodopa converted to dopamine with DOPA decarboxylase.

Question 27

What is noradrenalin made from?

Answer 27

Dopamine

Question 28

Which enzyme converts dopamine to noradrenalin?

Answer 28

Dopamine beta-hydroxylase.

Question 29

What is the rate limiting step in dopamine synthesis?

Answer 29

The conversion of tyrosine to levodopa.

Question 30

What does the mesocortical pathway do?

Answer 30

Projects dopamine from the ventral tegmental area to the cerebral cortex and limbic structures (nucleus accumbens) - linked to reward and motivation.

Question 31

What is the VTA?

Answer 31

Ventral tegmental area - alternative site, near to the substantia nigra, where dopamine neurons collect.

Question 32

What are the positive symptoms of schizophrenia?

Answer 32

+ Psychosis; hallucinations, delusions (of grandeur, control and persecution) + Thought disorder

Question 33

What are the positive symptoms of schizophrenia associated with?

Answer 33

The excess dopamine (transmission)

Question 34

What are the negative symptoms of schizophrenia?

Answer 34

- Lack of emotion - Inability to experience pleasure. - Social withdrawal - Poverty of speech

Question 35

What are the negative symptoms of schizophrenia associated with?

Answer 35

Prefrontal cortex damage.

Question 36

What is the dopamine hypothesis of schizophrenia?

Answer 36

- Schizophrenia occurs as a result of the action of agonists and antagonists of dopamine. - Positive symptoms result from excess dopamine transmission.

Question 37

What is the drug that is used against the positive symptoms of schizophrenia?

Answer 37

Chlorpromazine - blocks dopamine D-@ receptors.

Question 38

What is the effect that chlorpromazine has on neuroses and mood disorders?

Answer 38

Very little.

Question 39

What are antipsychotic medicines also referred to?

Answer 39

Neuroleptics.

Question 40

What can cause psychoses in people that do not even have schizophrenia?

Answer 40

Drugs which increase the transmission of dopamine. e.g Amphetamine.

Question 41

What are the short term consequences of drug treatment in schizophrenia?

Answer 41

- Parkinson's like symptoms

Question 42

What are the long term consequences of drug treatment in schizophrenia?

Answer 42

Abnormal, involuntary movements, especially of the tongue and face. = tardive dyskinesia.

Question 43

What are the negative consequences of treating Parkinson's disease?

Answer 43

- Dyskinesia | - Psychoses (visual & usually not scary)