19.3 Neuronal Disorders Flashcards
Wallerian degeneration is
Active process of retrograde degeneration of distal end of an axon resulting from nerve lesion or injury
Wallerian degeneration is caused by
Axonal injury (CNS or PNS)
What things occur during Wallerian degeneration?
Demyelination of the distal (axonal) end
Skeleton of the axon disintegrates
Debris cleared by macrophages
(Normal flow of materials from soma to the axon terminal is interrupted)
Demyelinating disease describes
Damage to protective myelin sheath surrounding nerve fibres
Demyelinating disease leads to
Slow/stopped nerve impulses
Multiple sclerosis is
Chronic autoimmune disease affecting CNS; immune system attacks myelin
What is multiple sclerosis? What causes it?
Abnormal immune response against the myelin sheaths around neurons in the brain, spinal cord and optic nerves resulting in weakness, lack of coordination and impaired vision and speech
Motor neuron disease
Progressive neurological disorder targeting motor neurons
Motor neuron disease typical progression
Weakness/muscle wasting of hands/arms legs followed by respiratory and digestive muscles
Name two CNS degenerative disorders
Alzheimers disease
Parkinsons disease
On the anatomical level, which regions are affected by Alzheimer’s disease?
Entorhinal cortex
Hippocampus
Cortical atrophy
On the cellular level, what is the pathology of Alzheimer’s disease?
Amyloid plaque deposition (A-beta)
Tau tangles
ApoE4/4
What type of disorder is ALS?
Motor neuron disease which affects both upper and lower motor neurons, affecting muscles of upper and lower limb, mouth and respiratory system
What are the symptoms of Alzheimers disease?
Progressive decline in memory (factual, short term and impaired word finding)
Visual and spatial disorientation
Altered personality
Agitation
Anxiety
Aggression
