W22-L2: Regulating Dopamine Levels

Question 1

In the extrapyramidal motor system acetylcholine and dopamine have what roles?

Answer 1

Acetylcholine: Excitatory input

Dopamine: Tonic inhibition

Question 2

Motor signs of parkinson’s disease

Answer 2

•  Tremor
•  Rigidity of limbs
•  Bradykinesia
•  Impairment of postural reflexes
•  Facial
–  Impassive, no blinking
•  Speech
–  Monotonous, hypophonic

Question 3

Non motor signs of parkinson’s disease

Answer 3

• Cognitive deficiencies
• Depression
• Raised anxiety levels
• Olfactory deficiencies
• Sleep disturbances
• Fatigue
• Sexual dysfunction
• Pain
• Bowel & bladder problems

Question 4

What is the cause of Parkinson’s disease and how much degradation is required?

Answer 4

Dopaminergic nerves in the substantia nigra degenerate, need 80% degeneration

Question 5

T/F There is asymmetric degradation of substantia niagral dopamine neurones in parkinson’s

Answer 5

True

Question 6

What is the management of parkinson’s disease?

Answer 6

Drugs provide symptomatic relief that attempt to Restore dopamine deficiency and restore dopaminergic / cholinergic balance in striatum.

Question 7

What does L-Dopa do?

Answer 7

Provide substrate for dopamine synthesis

Question 8

What do you give with L-Dopa?

Answer 8

An inhibitor of Peripheral Dopa decarboxylase to prevent L-Dopa’s peripheral metabolism

Question 9

What is a side effect of L-Dopa?

Answer 9

causes some of the dopaminergic neurones to die, possible due to increased ROS due to dopamine production from L-Dopa and these neurones can’t handle it

Question 10

When wanting to restore dopaminergic-cholinergic imbalance when are muscarinic receptor antagonists used?

Answer 10

Only in conjunction with L-Dopa