Degenerative Disorders Flashcards
Where does dengeneration occur in Parkinson’s?
SN compacta
Where does dengeneration occur in Alzheimer’s and pick disease?
The cortex
Where does dengeneration occur in Amyotropic lateral sclerosis?
Peripheral muscles
What is the main things of Alzheimer’s disease?
- cortex
- dementia
- gross: atrophy
- microscopic plaques and tangles
- hippocampus, language centers
What is the clinical picture of Alzheimer’s?
Most common cause of dementia in elderly (60)
- stages
Early: forgetfulness, mood/behavioral changes
Next: disorientation, memory loss, aphasia, loss of motor skills
5-10 years: Px profoundly disabled, mute, immobile, death from infection usually
What changes happen when a Px comes in for Alzheimer’s?
Hippocampus and frontal cortex
What is the morphology of AD?
Amyloid plaques - tortuous neurite, amyloid beta peptide
Tangles - tau, MAP2, ubiquitin
Other: gliosis, neuronal loss, cerebral amyloid in vessels
What do you view plaques and amyloid with?
Plaques - silver stain for cell processes too
Amyloid - Congo red - polarized light looks green
What are neurofibrillary tangles?
Tau tangles
Kills neurons
How do you diagnosis Alzheimer’s?
Clinically
- APP, aggregates are neurotoxicity and pro-inflammatory
Number of plaques and tangles link with symptoms
What is tau accumulation caused by?
A beta peptide (amyloid) abnormal
Comes from APP
How does B amyloid abnormality lead to tau accumulation?
B amyloid breaks microtubules
Allowing tau to be hyperphosphorylated and accumulate in the cell body
Not fully supported
What is Pick disease?
Frontotemporal lobar degeneration/dementia
What must you know in pick disease (FTLD)?
- Personality and language changes PRESENTATION
- severe atrophy of frontal and temporal lobe
- pick bodies containing tau protein
What is the progress of Pick disease?
60 or younger
- frontal lobe signs (personality) temporal signs (language)
- later dementia
What is a pick body?
Tau protein aggregation within neurons
Use silver stain
What is the main sign you see in Parkinson’s?
Trouble initiating voluntary movements
Mask like facees
Pill rolling tremor
What are the main things you need to know about Parkinson’s?
- degen of SN
- tremor, rigidity, bradykinesia
- Lewy bodies
- slightly shortened life span
What is Parkinsonism?
- masked facees
- stooped posture
- slowness of voluntary movement
- festinanting gait
- rigidity
- pill-rolling tremor
How do you test for Parkinson’s?
See if they respond to L-DOPA
Why is the SN dark?
There is melanin in it
What are Lewy bodies?
Melanin containing body
What is the Parkinson’s pathogenesis?
Alpha synuclein
What is ALS?
Lugarigs disease
What must you know about ALS?
- degeneration of motor neurons
- rapidly progressive weakness, spasticity, and dysphagia
- sensory and cognitive function are unaffected
- death within 2-3 years due to respiratory compromise
- peripheral muscles atrophy
What are clinical features of ALS?
Early: asymmetric hand weakness, arm/leg spasticity, twitching, slurred speech
Later: atrophy, fasciculations, creeping paralysis
Eventually: respiratory muscles involved (infection)
What is the pathogenesis of ALS?
- cause of motor neuron degeneration is not well understood
- SOD is mutated in inherited cases but lack of degeneration doesn’t seem to be the cause
- bottom line, degeneration often with toxic protein accumulation
SOD (superoxide dismutase)
What is the morphology of ALS?
- thin anterior roots of spinal cord
- degeneration of corticospinal tracts
- decrease in anterior horn neurons
- skeletal muscles atrophy
