Catecholamines

Question 1

what are the type of the dopamine receptors

Answer 1

Dopamine receptors are GPCRs

Question 2

what are the families of the D receptors

Answer 2

D1 Family

D2 Family

Question 3

explain the D2 Family

Answer 3

D2, D3, D4
- couple with Gi (inhibitory)
- located on presynaptic and/or postsynaptic neurons
- greater affinity for dopamine (may mediate tonic transmission)

Question 4

explain the D1 Family:

Answer 4

D1 and D5
- couple with Gs (excitatory)
- located on postsynaptic neurons
- lower affinity for dopamine (may require phasic transmission)

Question 5

how does ADHD products work

Answer 5

Stimulant products that boost norepinephrine and dopamine
neurotransmission by inhibiting their re-uptake by presynaptic neurons

Question 6

how does Methylphenidate work

Answer 6

Norepinephrine and dopamine reuptake inhibitor (NDRI)
- One of the first medications for ADHD (Ritalin)
- Higher affinity and likely more active for dopamine

Question 7

how does Atomoxetine work

Answer 7

• Norepinephrine, dopamine, and serotonin reuptake inhibitor
• Relatively newer medication for ADHD (Strattera)
• Affinity for norepinephrine > serotonin > dopamine

Question 8

what is the role of the dopamine in the schizo

Answer 8

Dopamine involved in the postulated pathology of schizophrenia.
- evidence for greater expression of the D2 receptors in patients
- efficacy of D2 receptor antagonist antipsychotics correlates
with D2 receptor affinity

Question 9

how does haloperidol work

Answer 9

antagonist at DA > 5-HT receptors
- potential for extrapyramidal adverse effects

Question 10

how does olanzapine work

Answer 10

antagonist at DA ~ 5-HT receptors
- lower potential for extrapyramidal adverse effects

Question 11

what is the pathology of the Parkinson

Answer 11

• Progressive neurodegenerative disease
• Loss of dopaminergic neurons in the substantia nigra pars compacta
• Dysregulation of basal ganglia motor circuits

Question 12

how does Levodopa (L-DOPA) work

Answer 12

• precursor to dopamine; has been used for decades
• majority of dose remains outside of the CNS, and conversion to
  dopamine induces adverse effects (nausea and vomiting)
• often co-administered with an aromatic L-amino acid decarboxylase
  inhibitor that stays in the periphery (e.g. carbidopa)

Question 13

what are the Dopamine agonists in the parkinson

Answer 13

pramipexole and ropinirole: agonists at D2, D3, and D4 receptors
- adverse effects: nausea, hallucinations

Question 14

where does Norepinephrine (Noradrenaline) produces

Answer 14

– Locus Coeruleus

Question 15

give two ex for SNRIs

Answer 15

Venlafaxine (Effexor)
Duloxetine (Cymbalta)