Dopamine

Question 1

Dopamine has….

Answer 1

excitatory and inhibitory influences depending on post synaptic receptor
- Inactivated by reuptake

Question 2

Dopamine appears to be involved in

Answer 2

learning, attention, movement and reinforcing effects of drugs

Question 3

Precursors, respectively

Answer 3

• tyrosine – essential amino acid, must be obtained from diet
• L-dopa
• Dopamine
• Norepinephrine

Question 4

Several systems of da neurons in brain; 3 most important:

Answer 4

Nigrostriatal
Mesolimbic
Mesocortical

Question 5

Nigrostriatal

Answer 5

a. cell bodies in substantia nigra
b. project to neostriatum, i.e. caudate and putamen, part of basal ganglia
c. involved in control of movement

Question 6

Mesolimbic

Answer 6

a. cell bodies in ventral tegmental area
b. project to limbic system: nucleus accumbens (important in the reinforcing effects of substance use)
c. amygdala and hippocampus (important for learning & memory)

Question 7

Mesocortical

Answer 7

a. ventral tegmental area
b. project to prefrontal area
c. important for judgment, planning, strategy formation for problem-solving and working memory

Question 8

Parkinsons

Answer 8

• dopamine does not cross bbb

- treated with L-dopa

Question 9

6. Various types of da receptors and all are metabotropic

Answer 9

• D1 – exclusively post-synaptically

- D2 – pre and post synaptic

Question 10

Drugs related to dopamine

Answer 10

• amphetamine, cocaine, Ritalin – blocks reuptake and causes the transporters to run in reverse so da and ne are released

Question 11

Production of DA is regulated by the enzyme…

Answer 11

MAO in the presynaptic membrane where it destroys excess da

• MAO inhibitors old antidepressants
• MAO also deactivates amines in food; rise in BP occurs with accumulation of amines

Question 12

symptoms of schizophrenia are reduced by

Answer 12

Dopamine antagonist drugs because Chlorpromazine or Thorazine binds to the D2 receptor