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Flashcards in Basal Ganglia Deck (11):
1

What does the basal ganglia consist of ?
(also called the extrapyramidal system
0

striatum (caudate and putamen), globus pallidus, substantia nigra, and the subthalamic nucleus

2

Hypokinesia

Parkinsons
motor activity is reduced or slowed, except for resting tremor

3

Hyperkinesia

choreoathetosis or hemiballismus
-excessive, involuntary movements

4

Parkinson's disease

loss of dopaminergic neurons in the substantia nigra

-net increased inhibitory output of the GPm to the ventrolateral thalamic motor nuclei--reduction in stimulation of the motor cortex

5

Hemiballismus

destruction of the subthalamic nucleus
-net decreased inhibitory output of the GPm

6

Huntington's disease

loss of indirect pathway putaminal neurons to the lateral globus pallidus
-net decrease inhibitory output of GPm
--choreoathetosis

7

What are the clinical signs of Parkinson's disease?

*1. resting tumor
-pill-rolling
*2. rigidity
cogwheeling
*3. bradykinesia
*4. impaired postural reflexes
-balance instability (light pushing)
5. masked facies
6. hypophonic speech-hoarse, soft and difficult to understand
7. micrographia
8. constipation, bladder dysfunction, or orthostatic hypertension
9. REM behavior sleep disorer

8

How is parkinson's diagnosed?

clinically
-at least 2 of the 4 primary clinical signs should be present and atypical features should be absent
-improvement with first dopaminergic medication

9

What do you see in the neurons of parkinson's?

loss of pigmented dopaminergic neurons in the substantia nigra
-alpha synuclein positive-Lewy bodies

grossly substantia nigra and locus ceruleus appear pale

10

Treatment of PD

1. Levodopa-the most effective
2. combined with carbidopa (limits catabolism of levodopa)
3. COMT inhibitor -smoothes out undesirable motor fluctuations
4. MAO type B inhibitor
-extend effects of dopamine
5. anticholinergic-control of resting tremor
6. dopamine agonists

electrode into subthalamic nucleus to inhibiting it by means of repetitive electrical stimulation

11

Huntington's disease

choreoathetosis, dementia, and behavior syndromes
-multiple trinucleotide repeats in huntingtin gene on chromosome 4

-caudate atrophy and frontal horns of the lateral ventricles appear relatively enlarged

treatment: dopamine antagonists and antidepressants and catecholamine depleter