Parkinson's Disease Flashcards
what are the 3 nuclei of the basal ganglia?
1- caudate
2- putamen
3- globus pallidus
what are the 2 brainstem nuclei?
1- substantia nigra
2- subthalamic nucleus
what are the functions of the basal ganglia?
Direct Loop:
cortex–> putamen–> globus pallidus–> thalamus
Indirect Loop:
cortex–> putamen–> globus pallidus–> subthalamic nucleus –> thalamus
In general, the direct pathway activates the thalamocortical pathway and the indirect pathway inhibits it.
The appropriate “gain” of the system is adjusted and information is sent to the muscles by way the thalamus and motor cortex.
what is the physiology of the BG?
The BG would have a role in cortical activation and modulation
One Theory:
- under active direct pathway and/or an overactive indirect pathway= decrease activation of the cortex and bradykinesia/akinesia
- Overactive direct pathway and/or an under active indirect pathway= extraneous movements
what are 3 neurotransmitters?
1- Dopamine (DA)
2- Acetylcholine (ACh)
3- Gamma-aminobutryric (GABBA)
what is dopamine?
produced in the substantia nigra and both (-) and (+)
+ to the neurons in the direct pathway
- to the neurons in the indirect pathway
what is ACh?
neurotransmitter of the caudate and putamen
(-) the action of dopamine
what is GABBA?
inhibitory neurotransmitter bound throughout the brain
what is the role of the BG?
1- automatic movement- involved in the preparatory stages but not in the excitation of movement
2- movement initiation and preparation- generator for ramp movement
3- postural adjustments
4- perception and cognitive function- procedural learning
what is declarative learning?
can explain how to do it
what is procedural learning?
knowing how to do something
what are symptoms of parkinsons?
1- rigidity (cogwheel or lead pipe)
2- bradykinesia
3- tremor
4- postural instabilty
5- festinating gait
6- freezing
7- attentional and cognitive deficits
8- dysphagia
9- micrography
10- depression
11- bronchopneumonia (complication)
what is bradykinesia?
all aspects of movement including initiation, alteration in direction and the ability to stop and begin a movement
spontaneous or associated movements such as arm swing, smiling to a funny story
difficulty performing simultaneous or sequential movements
difficulty with transition between movements
what are resting tremors?
4-7 beats/sec in extremities and trunk (postural tremors)
postural stability:
leads to increased episodes of falling
- flexed posture
- lack of equilibrium and righting response
- decrease in trunk rotation
ineffective sensory processing
decrease anticipatory postural adjustments
what is a festinating gait?
characterized by a progressive increase in speed and shortening of stride
loss of heel toe progression–> decreased ability to step over obstacles or walk on uneven surfaces
what is freezing?
treatment is to stop weight shift side, count to 5-10, get reorganized and then move ahead or give patient an imaginary line or real object to step over
what attentional and cognitive deficits usually occur with Parkinson’s?
inability to shift attention
inability to quickly access “working memory”
difficulty with visuospatial perception and discrimination
impaired procedural learning
dementia
what is dysphagia?
difficulty swallowing
what are medical management options for parkinson’s?
dopamine replacement
COMT inhibitors
dopamine agonist
anticholinergics
apomorphine
MAO-B inhibitors
others
what are dopamine replacement?
Sinemet
Sinemet CR
Stalevo
Parcopa
what are COMT inhibitors?
Comtan (Entacapone)
Tasmar (Tolcapone)
decreases the breakdown of l-dopa in the blood
what are dopamine agonists?
Parlodel (Bromocritine) Requip Permax (Pergolide) Mirapex Neupro APOKYN injection
meds that act like dopamine
The dopamine agonist binds to and activates the stratal dopamine receptors
what are anticholinergics?
Artane (trihyxuphenidyl)
Cogentin (benztropine)
decrease ACh –> increase DA
These meds are most helpful for tremors and stiffness and less for slowness, balance and gait deviations
