Disorders of Basal Ganglia

Question 1

dec inhibition of direct pathway, inc stimulation of indirect pathway of GPm

Answer 1

Parkinsons

Question 2

net inc inhibitory output of GPm

Answer 2

Parkinsons

Question 3

net dec inhibitory output of GPm

Answer 3

hyperkinetic disorders like hemiballismus and Huntington’s

Question 4

destruction of subthalamic nuc lowers GPm inhibitory output

Answer 4

hemiballismus

Question 5

loss of indirect pathway increases inhibition of subthalamic nuc and lowers GPm inhibitory output

Answer 5

Huntington’s

Question 6

inc DA doses for parkinson’s tx can give

Answer 6

hyperkinesia (choreoathetosis or dystonia)

Question 7

tremor when patient is sitting/reclining and often involves distal upper limbs asymmetrically

Answer 7

resting tremor

Question 8

tremor exacerbated by stress

Answer 8

resting tremor

Question 9

supinating pronating tremor of hands

Answer 9

pill rolling tremor

Question 10

constant resistance/inc tone on passive movement

Answer 10

rigidity

Question 11

rachety/jerky feeling created by tremor when a rigid limb moves

Answer 11

cogwheeling

Question 12

balance instability while standing/walking that’s out of proportion to degree of rigidity

Answer 12

impaired postural reflexes of Parkinson’s

Question 13

lewy bodies

Answer 13

seen in parkinsons - alpha synuclein positive, eosinophilic, cytoplasmic inclusions

Question 14

alpha synuclein positive, eosinophilic, cytoplasmic inclusions

Answer 14

lewy bodies

Question 15

pale regions in parkinson’s

Answer 15

locus ceruleus and substantia nigra

Question 16

3 synucleinopathies

Answer 16

parkinson’s, lewy body dementia, multiple system atrophy

Question 17

precursor of dopamine

Answer 17

levodopa/L-dopa

Question 18

decarboxylase inhibitor

Answer 18

carbidopa

Question 19

effectiveness of levodopa over time

Answer 19

each does provides less asymptomatic time as the disease progresses

Question 20

entacapone

Answer 20

COMT inhibitor

Question 21

DA agonists w/ dec dyskinesia side effects

Answer 21

ropinirole and pramipexole

Question 22

deep brain stimulation for parkinson’s

Answer 22

electrode put on subthalamic nuc that inhibits it by repetitive stimulations

Question 23

dementia, behavioral syndromes, and involuntary movements

Answer 23

huntington’s

Question 24

huntington’s genetics

Answer 24

autosomal dominant

Question 25

huntingtin gene

Answer 25

chromosome 4

trinucleotide repeats

Question 26

neurons lost in huntington’s

Answer 26

putaminal GABA-ergic neurons (early)

cholinergic neurons (late)

Question 27

MRI/CT findings of huntington’s

Answer 27

frontal horns of lateral ventricles enlarged, atrophy of caudate

Question 28

tx to dec choreoathetosis

Answer 28

tetrabenazine (catecholamine depeleter) and D2 antagonists