Parkinson and Huntington Flashcards
what happens in parkinson
direct pathway is lost from substantia nigra pars compacta, indirect pathway wins which is inhibitory
What bodies do you see in Parkinson in the brain and waht are they made from? WHat other conditions do they also present
Lewy bodies
protein α-synuclein
Other dementias
what sort of imaging can you use to monitor the progession of Parkinson
DaT (dopamine transporter) scan
core motor symptoms of parkinson
tremor, flexed posture, bradykinesia, rigidity, parkinsonian mask
some non-motor features of parkinson
olfactory dysfunction
depression
psychotic symptoms
cognitive dysfunction
dementia (late phase)
sleep disturbance
bladder and bowel dysfunction
speech and language changes
non-motor features of parkinson can precede the motor features by how long
a decade
which gene do you have to remember -> familial parkinson? WHat does it do
SNCA - intereferes with alpha synuclein processing
dopamine is susceptible to what chemical process
oxidation
what are monoamines
dopamine
seratonin
adrenaline
noradrenaline
from what is dopamine synthesised what are the enzymes
what are dopamine receptors(type) and what to they do
GPCR
D1 - activation
D2 - inhibition
adverse effects of L-Dopa (6)
Nausea/vomiting
Postural hypotension
Psychosis
Impulse control disorders (more frequent with use of dopaminergic agonists)
Dopamine dysregulation syndrome
Excessive day-time sleepiness
how is dopamine metabolised what are the enzymes
after 3-5 years of L-DOpa what is most common complication
On-off motor freezing
newer tx for parkinson
robotics for posture
deep brain stimulation
where is huntington which chromosome
huntingtin protein chormosome 4
if a person has >60 CAG repeats in huntington, what does that infer
juvenile (<40) onset
which protein aggregates in huntington
huntingtin
which pathways are compromised in Huntington
striato-pallidal and striato-nigral
symptoms of huntington
Choreic movement (early to mid-stage disease)
Gait abnormalities
Lack of coordination
Cognitive impairment: poor attention, memory difficulties
Psychiatric disturbances
Sleep disturbance
Weight loss
pharmacotherapy for huntington
Vesicular amine transporter inhibitor: tetrabenazine
Antidopaminergic (antipsychotic) drugs: haloperidol, olanzapine
Antidepressant drugs: citalopram, fluoxetine, sertraline
Mood stabilisers: carbamazepine, lamotrigine
pharmacotherapy for parkinson
- 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)
What contrast medium on dat scan
Ioflupane 123
What should/shouldn’t you see on dat scan
Should see commas
Shouldn’t see full stop
