Theory - Parkinsons 02 Flashcards
When the final GABAurgic neuron (the one in the thalamus) fires, what occurs, inhibition or disinhibition?
Inhibition
Which causes inhibition and which causes disinhibition, and odd or an even number of GABAurgic neurons?
Odd - inhibition
Even - disinhibition
On the GABAurgic neuron in the excitatory pathway what type of dopamine receptors do you have?
D1 which are excitatory, so dopamine via the D1 receptors puts on the gas
On the GABAurgic neuron in the indirect pathway what type of dopamine receptors do you have?
D2 which are inhibitor, so dopamine via the D2 receptors takes off the brakes
What does D1 plus D2 agonists give you?
It gives you maximum movement
Is acetylcholine like putting on the gas or the brakes?
The brakes, acetylcholine excites the pathway which is inhibitory
If you think of it as a balance, on one side you have dopamine via D1 and D2 and on the other side you have acetylcholine, which increases movement and which decreases movement?
Dopamine increases movement (go) and acetylcholine decreases movement (no-go)
What happens if you wipe out dopamine producing neurons?
The balance shifts towards acetylcholine(no-go). This is the problem in Parkinson’s disease.
Which neurons are pyramidal and which are extrapyramidal?
Pyramidal = Glutamate neurons Extrapyramidal = GABAurgic, Dopaminergic, Acetylcholine neurons
Antipsychotics cause effects on what system?
The extrapyramidal system (EPS effects)
In which direction is the balance shifted in hyperkinesia?
Toward dopamine (Choreatic disorders, Tourette’s, Hyperactivity disorders, diskinesias)
In which direction is the balance shifted in hypokinesis?
Toward acetylcholine (Parkinson’s, dystonia)
