Parkinson's disease

Question 1

Pathophysiology: Parkinson’s disease (original)

Answer 1

Loss of dopamine reduces excitatory output to the striatum of the direct pathway causing increase in inhibitory output to the thalamus

Also, Loss of dopamine fails to inhibit the striatum of the indirect pathway resulting in producing more inhibitory output to the thalamus.

Therefore there is excessively increase in inhibitory output to the thalamus from both pathways causing less excitatory output to the cortex.

Question 2

Definition: Parkinson’s disease

Answer 2

a progressive degenerative disorder of the CNS resulting from death of dopamine-generating cells in the substantia nigra of the Basal ganglia.

Question 3

Cause & Risk factors: Parkinson’s disease

Answer 3

• idiopathic

- age (over 60), gender (male>female), exposed to toxins (pesticides), family history, traumatic injury

Question 4

Epidemiology: Parkinson’s disease

Answer 4

1 in 500 in NZ

1% of over 60 years old

Question 5

Pathophysiology: Parkinson’s disease

Answer 5

Loss of dopamine fails to facilitate the direct pathway and inhibit the indirect pathway of the striatum, resulting in excessive increase of inhibitory output to the thalamus causing less excitatory output to the cortex

Question 6

5 major signs of PD

Answer 6

-Rigidity
-Tremor
-Bradykinesia
-Postural instability
-Cognitive & Behavioural change (difficulty initiating movement, memory)
Others: stone mask like face, stooped posture

Question 7

Medical management: PD

Answer 7

medication:

• Dopamine procursors (boost production in substantia nigra)
• Levadopa (replaces depleted dopamine => improves bradykinesia & rigidity)
• Dopamine agonist (increase uptake of receptors in striatum)