Lean Jonker 31668577 (SU 8)

Which two main groups of drugs are important in the treatment of Parkinsonism?

• Drugs that increase Dopamine’s Activity
• Drugs that decrease cholinergic activity

In what way does amantadine act as an anti-parkinsonism drug?

3 ways of action

• Metaffinoid potentiator of Dopamine (Increase Dopamine release and Syntheis & Blocks the reuptake of DA)
• NDA Antagonist
• Adenosine A2 Antagonist

Discuss the mechanisms of action of the anti-parkinsonism drugs that indirectly increase dopamine concentration.

L-DOPA (Increased L-DOPA causes an increase in dopamine synthesis causing a increase in dopamine that is available in the body) Needs to be used in combination with CARBIDOPA or BENSERAZIDE

AMABTADINE (See above question)

RASAGILINE & SELEGILINE  & SAFINAMIDE (MAO-B inhibiter, thus prevents the breakdown of breakdown of dopamine to DOPAC)

ISTRADEFYLIN (Adenosine A2 Antagonist)

ENTACAPONE (COMT-Inhibitor, thus prevent the breakdown of Dopamine to 3-MT)

Which of the dopamine agonists are ergot derivatives and which are not?

ERGOT DERIVATEVES	Not Ergot derivates
Bromocriptine	Pramipexole
	Ropinirole

List the specific dopamine receptors that are stimulated by each agonist.

Bromocriptine – D2

Pramipexole -D3

Ropinirole-D2

Which of these drugs are classified as neuron protecting drugs?  What does this mean?

Pramipexole, it means that the drug counteracts the degenerative effect of Parkinson’s Syndrome. Thus, protecting the brain neurons from further damage.

What is the importance of monoamine oxidase B (MAO-B) selective drugs in the treatment of Parkinsonism?

The antagonist of inhibitory drugs for MAO-B would prevent the metabolism of Dopamine, thus increasing DA’s plasma levels and Bioavailability. This will also in effect reduce the side effect seen due to PD.

How do the COMT-inhibitors act in Parkinsonism?

In Much the same way is MOA-B initiators, the inhibit the action of COMT leading to a decrease in 3-OMD (a metabolite of dopamine that competes for active transport from the periphery to the brain via the BBB). This lead to an increase influx of L-DOPA into the brain thus a increase in Dopamine plasma levels in the brain.

How does istradephyline act?

It is an Adenosine A2-A Antagonist. A blockage of adenosine receptors causes an increase in Dopamine’s activity.

Discuss the MOA of safinamide

• MAO-B inhibition
• Dopamine reuptake inhibition presynaptic ally
• Decrease in Glutamate release.