Week 5 Flashcards
Donepezil, Galantamine, Rivastigmine
1. name of these drug types
2. MOA?
3. Used for what disorder?
- Cholinesterase Inhibitors
- Inhibits acetylcholinesterase to boost levels of ACh -> treats cognitive symptoms of Alzheimers
- Alzheimers
Donepezil, Galantamine, Rivastigmine
1. At what stage of AD are these used for?
- Donepezil - at all stages (first line drug)
- Rivastigmine - at all stages (first line drug)
- Galantamine - mild to moderate dementia of AD
Donepezil, Galantamine, Rivastigmine
(Cholinesterase Inhibitors)
1. What are the side effects
2. What are some contraindications
- Nausea, dizzy, insomnia; loss of appetite, weight loss; bradycardia
- Don’t use if taking anticholinergic drugs - opposite effect of what these drugs are trying to do
Memantine
1. What type of drug is this
2. MOA
3. What disease is this used for?
- NMDA receptor antagonist
- Blocks NMDA which are usually activated by excitatory glutamate (only treats cognitive symptoms of AD) -> too much glutamate cuases too much neural excitation which is most likely a reason for neuronal injury in alzheimers dx
- Alzheimer’s disease
Memantine
1. What stage of AD is this best used for?
2. Side effects
3. Contraindications
- moderate to severe AD patients
- dizziness, confusion, hallucination
- Hypersensitivity to memantine
Aducanumab
1. What type of drug is this?
2. MOA
3. What disease is this used for?
- Anti-amyloid plaque antibody
- monoclonal Ab against aggregated forms of amyloid beta. Ab surround aggregated amyloid beta and recruit activated microglia -> phagocytosis
- Alzheimers disease
Aducanumab
1. What stage of AD is this used for?
2. side effects
- mild AD
- headache, confusion, dizziness, falls, vision change
what is the difference between declarative and non-declarative long term memory?
- Declarative: these are facts and events
- Non-declarative: these are skills, doesn’t require conscious thought and allows people to do things by rote
- Describe Long term potentiation
- When does this happen (declarative or non-declarative)
- strengthening of a synaptic connection that happens when the synapse of one neuron repeatedly fires and excites another neuron
-> Ca2+ flux through NMDA receptor channels initiate LTP - When forming declarative long term memories
How do cells in the brain work together to create classical conditioning in non-declarative long term memory? (hint: pukinje cells are involved)
- Unconditioned stimulus (ex: dog food) signals come from climbing fibers in from inferior olive
- Conditioned stimulus (ex: bell) signals come from mossy fibers (parallel fibers to climbing fibers) in from pontine nuclei in brainstem
- Both signals go into purkinje fibers -> when stimuli come in at the same time eventually you get long term depression of parallel fiber EPSP after beginning to pair US and CS
** AMPA receptors are being removed from parallel fiber synapse (mossy fibers) and allows US to occur in response to CS alone **
Alzheimer’s Disease
1. Degeneration of what?
2. Loss of what NT?
3. Gross changes in brain (3)
- cortex
- loss of ACh cortical activity
- gyri narrow and sulci widen + hydrocephalus ex vacuo (image) + hippocampal atrophy
Alzheimer’s Disease
1. clinical features (5)
- slow-onset of memory loss
- loss of learned motor skills and language
- behavior and personality changes
- patient becomes mute and bedridden
- No focal neuro deficits
Alzheimer’s Disease Genetics
1. Sporadic vs Familial which is more uncommon
2. what genetic mutation in sporadic type increases risk vs which one decreases risk
- familial late onset is uncommon and familial early onset is rare
- ApoE - E4 allele increases risk —- ApoE - E2 allele decreases risk
Alzheimer’s disease
1. Familial early onset (rare) - is seen with what genetic mutations?
2. Why do those with down syndrome have higher risk of AD as well?
- mutation or duplication of APP gene on chromosome 21 OR mutation in presenilin 1
- three chromosome 21 is where APP gene is found - increases risk of AD by age of 40
Alzheimer’s Disease
1. What is found in histology of brain (2)
2. What does this lead to?
- beta amyloid plaques
- Neurofibrillary tangles (collection of tau proteins inside neuron cell body)
- Neuritic plates - amyloid core surrounded by dystrophic neurites
–> this all leads to loss of neurons and gliosis
Pick Disease
1. What is it?
2. Pathophysiology?
- rare cause of dementia that degenerates frontal and temporal lobes causing changes in personality and aphasia
- pick bodies (spherical tau proteins) - inside neurons
Pick disease
1. Is it inherited?
2. Hallmark symptoms
3. Gross anatomy descriptions of brain (2 main ones)
- It is mostly sporadic
- changes in personality/behavior (frontal) and aphasia (temporal)
- Cortical atrophy in frontal and temporal lobes -> “knife-edge” appearance in these areas, ventricular dilation, etc
Parkinson Disease
1. What does histology show?
- Shows lewy bodies (cytoplasmic inclusions - which are deposits of alpha-synuclein) in substantia nigra of basal ganglia
Lewy Body Dementia
1. Pathophysiology
2. Triad symptoms?
- Collection of lewy bodies (deposits of alpha synuclein) in cortex -> the build up of this causes dementia
- Dementia, Parkinson symptoms, Hallucinations
Dementia occurs before parkinson sx
In parkinson, lewy bodies are in basal ganglia
Chronic Traumatic Encephalopathy (CTE)
1. Sx
2. pathophysiology
3. Changes to brain (gross) (4)
- Inattention, mood and behavior disturbances, confusion, memory loss, demention, parkinsonism
- Brain damage due to repetitive truamatic brain injuries
- Cerebral atrophy, enlarged ventricles, thinning of corpus collusim, depigmentation of substantia nigra
Prion Disease (Spongiform Encephalopathy)
1. Types
2. Most common subtype
- sporadic, inherited (PRNP gene on chromosome 20), transmitted
- Creutzfeldt-Jakob Disease
Creutzfeldt-Jakob Disease (A type of prion disease)
1. Presentation (symptoms) (3)
2. Pathophysiology?
- Rapidly progressive dementia, Myoclonus (muscle jerk), Ataxia
- PrPc (normal) -> changes to PrPsc (abnormal);; with more abnormal/pathologic protein it will accumulate in neurons, damage neurons, and causes spongy holes in brain matter
Prion Disease
1. Changes to brain (gross and histology)
- some degree of cerebral atrophy with hippocampus spared
- Histo: spongiform change (holes in neuronal processes/neurites, neuronal loss, reactive gliosis, absence of inflammation
- What are association fibers in cortex
- cerebral fibers that have their origin and termination within the cortex and in the same hemisphere
- What are commissural fibers in cortex
- cerebral fibers that have their origin and termination within the cortex but in the opposite hemisphere
- What are projection fibers in cortex
- fibers connect the cortex to the subcortical regions
What lobes are useful in visual cortical system?
- mostly occipital but also the parietal and temporal lobe
Meyer’s Loop
1. Where is it found?
2. What is its function?
- temporal lobe
- It is made up of the dorsal and ventral stream - essential for visual sense. (as seen in image)
- Function of the Ventral stream of Meyer’s Loop
- Function of the Dorsal stream of Meyer’s Loop
- analyze what an object is, such as form and color
- where the object is, such as position, speed, and motion
- Lesion to the upper V1 of primary visual cortex causes [inferior/superior] quadrantopsia
- Lesion to the lower V1 of primary visual cortex causes [inferior/superior] quadrantopsia
- inferior - meaning bottom of their visual field is lost
- superior - meaning the top of their visual field is lost
Language processing
1. Speech skils that are left hemisphere dominant
2. Speech skils that are right hemisphere dominant
- understanding and producing speech (depends on wernicke and brocas areas respectively)
- emotion and affective elements of speech -> with lesions a person may not be able to detect these in someone else’s speech
- Dominant half of brain includes more skills for…
- Non- Dominant half of brain includes more skills for…
- language, skilled motor function, arithmetic
- prosody, visual spatial analysis, musical ability, sense of direction in space