Parkinson's disease

Question 1

Parkinsons disease definition

Answer 1

Movement disorder due to dopamine deficit

Question 2

Affected brain areas

Answer 2

Cell death in dopaminergic neurons

Lewy bodies with alpha-synuclein aggregation in the cell body of neurons

Question 3

Pathology

Answer 3

Stage 1+2 have not many symptoms
Stage 3+4 show rigidity, tremor and instability
Stage 5+6 show memory impairment, disturbed sleep, delirium

Question 4

How is dopamine synthesized?

Answer 4

Tyrosine gets converted to DOPA wich gets converted to Dopamine

Question 5

What pathways are there?

Answer 5

1. Nigrostriatal pathway (Motor control)
2. Mesolimbic pathway (Behaviour)
3. Mesocortical pathway (Behaviour)
4. Tuberohypophyseal pathway (endocrine control)

Question 6

How do we restore dopamine activity?

Answer 6

Levodopa can perform the same functions, but needs carbidopa to reach the brain in high enough quantities

GI side effects because it ends up in the gut

Question 7

Name some dopamine receptor agonists

Answer 7

Bromocriptine (D2)

Pamipexole (D3)

Ropinirole (D2, high affinity)

Question 8

How do MAOi help PD?

Answer 8

MAO metabolizes dopamine so less dopamine is available. Inhibiting this increases dopamine levels

Question 9

Name some MAOi

Answer 9

Selegiline, rasagiline

Question 10

How do COMPi help PD?

Answer 10

Inhibition of metabolism of dopamine to 3-OMD increases dopamine levels

Question 11

Name some COMPi

Answer 11

Entacapone, tolcapone