Parkinson and Huntington

Question 1

what happens in parkinson

Answer 1

direct pathway is lost from substantia nigra pars compacta, indirect pathway wins which is inhibitory

Question 2

What bodies do you see in Parkinson in the brain and waht are they made from? WHat other conditions do they also present

Answer 2

Lewy bodies
protein α-synuclein
Other dementias

Question 3

what sort of imaging can you use to monitor the progession of Parkinson

Answer 3

DaT (dopamine transporter) scan

Question 4

core motor symptoms of parkinson

Answer 4

tremor, flexed posture, bradykinesia, rigidity, parkinsonian mask

Question 5

some non-motor features of parkinson

Answer 5

olfactory dysfunction
depression
psychotic symptoms
cognitive dysfunction
dementia (late phase)
sleep disturbance
bladder and bowel dysfunction
speech and language changes

Question 6

non-motor features of parkinson can precede the motor features by how long

Answer 6

a decade

Question 7

which gene do you have to remember -> familial parkinson? WHat does it do

Answer 7

SNCA - intereferes with alpha synuclein processing

Question 8

dopamine is susceptible to what chemical process

Answer 8

oxidation

Question 9

what are monoamines

Answer 9

dopamine
seratonin
adrenaline
noradrenaline

Question 10

from what is dopamine synthesised what are the enzymes

Answer 10

Question 11

what are dopamine receptors(type) and what to they do

Answer 11

GPCR
D1 - activation
D2 - inhibition

Question 12

adverse effects of L-Dopa (6)

Answer 12

Nausea/vomiting
Postural hypotension
Psychosis
Impulse control disorders (more frequent with use of dopaminergic agonists)
Dopamine dysregulation syndrome
Excessive day-time sleepiness

Question 13

how is dopamine metabolised what are the enzymes

Answer 13

Question 14

after 3-5 years of L-DOpa what is most common complication

Answer 14

On-off motor freezing

Question 15

newer tx for parkinson

Answer 15

robotics for posture
deep brain stimulation

Question 16

where is huntington which chromosome

Answer 16

huntingtin protein chormosome 4

Question 17

if a person has >60 CAG repeats in huntington, what does that infer

Answer 17

juvenile (<40) onset

Question 18

which protein aggregates in huntington

Answer 18

huntingtin

Question 19

which pathways are compromised in Huntington

Answer 19

striato-pallidal and striato-nigral

Question 20

symptoms of huntington

Answer 20

Choreic movement (early to mid-stage disease)
Gait abnormalities
Lack of coordination
Cognitive impairment: poor attention, memory difficulties
Psychiatric disturbances
Sleep disturbance
Weight loss

Question 21

pharmacotherapy for huntington

Answer 21

Vesicular amine transporter inhibitor: tetrabenazine

Antidopaminergic (antipsychotic) drugs: haloperidol, olanzapine

Antidepressant drugs: citalopram, fluoxetine, sertraline

Mood stabilisers: carbamazepine, lamotrigine

Question 22

pharmacotherapy for parkinson

Answer 22

• L-DOPA (levodopa) is a biosynthetic precursor – is combined with peripherally acting DOPA decaboxylase inhibitors (e.g.carbidopa, benserazide)

  - Dopaminergic agonists: ropinirole, pramipexole, rotigotine, bromocriptine, cabergoline…
      	Rotigotine:  agonist which can be used as transdermal patch
      	Apomorphine: agonist which can be used as an infusion, for major motor fluctuations

*MAOB monoamine oxidase b inhibitors (protect residual dopamine against oxidation)
- rasagiline, selegiline, safinamide

*COMT inhibitors (used in combination with L-DOPA, to enhance its effects)
- entacapone, tolcapone

*Anticholinergic (antimuscarinic) compounds (dopamine loss leads to hyperactivity of cholinergic cells)
- orphenadrine, procyclidine, trihexyphenidyl

Amantadine (inhibits dopamine reuptake, increases dopamine release, also weak antagonist at NMDA glutamate receptors)

Question 23

What contrast medium on dat scan

Answer 23

Ioflupane 123

Question 24

What should/shouldn’t you see on dat scan

Answer 24

Should see commas
Shouldn’t see full stop