Cannabis Flashcards
What are some environmental triggers for MS
Infection (EBV, HERV)
Vitamin D levels
Smoking
What is the major gene of MS
HLA-DR
Briefly state mechanism behind MS
Autoimmune mediated CNS confined disease of demyelination
What glial cell does MS affect
Oligodendrocyte
What is seen in a brain of somebody with MS
- MS plaques
- Mononuclear cell infilitration
- Lesions
What is meant by ‘lesions in space and time’
Space= lesions are in different places throughout the brain Time= lesions are different ages
What is the first lesion in MS associated with?
Where inflammation occurs around the blood vessel- immune system is not working
What courses can MS follow
- Relapsing and remitting
- Secondary progressive
- Primary progressive
Which course of MS can’t be treated
Primary progressive
What is second lesion in MS associated with
Demyelination
What are shadow plaques associated with
Repear
Shorter node of Ranvier and thinner myelin
What happens if you don’t remyelinate the nerve
Vulnerable to death because no myelin is very damaging to cells- fired to death
What are the earliest features of MS (pre active lesion)
Activated microglial accumulates
Alerts the vasculature
What are the features of an active lesion
Lymphocytes arrive through blood vessel
Form an acute lesion
What are the features of a chronic active lesion
Lymphocytes eat out
Active rim is present- seen on MRI
Macrophages full of lipid droplets on edge
What are the features of a chronic inactive lesion
Demyelination
Astrocytes move in and form scar- gliosis
OR oligodenrocyte precusor cells move in and form a shadow plaque
OR axonal loss/ death
What happens to ventricles in MS
They expand due to accelerated rate of nerve loss
What is main aim of treating MS
Prevent lesions from arising in the nervous system
2 approaches to treat MS
Escalation- drugs with low efficacy but low side effects, if disease still active switch to drugs with high efficacy high side effects
Induction therapy- a few treatments of highly effective drugs which you watch and monitor. After a few cycles some people don’t seem to need drugs
What happens if people accumulate damage and deficits
Start to display signs and symptoms
What are signs and symptoms due to
Conduction block
Demyelination
Loss of axons and neurons
Loss of synaptic plasticity
What are the signs and symptoms of MS
Blindness Nystagmus Fatigue Pain Tremor Spasms and spasticity Bladder problems Incontinenece Sexual problems Motor defects Cognitive defects
What signs and symptoms respond to cannabis
Pain
Spasms and spasticity
Define spasticity
Exaggerated stretch response- if you try to move the limb it will cause a spasm
What causes spasticity
Damage to circuitry: either too much excitation or too little inhibition
How do you treat spasticity if theres too much excitation
Nabiximols
Tizanidine
Anti-convulsants
What are the side effects of drugs that treat spasticity
Sedation
How do you treat spasticity if theres too little inhibition
Baclofen (GABA agonist)
GABApentin
Benzodiazepines
Mechanism of action of baclofen
GABAb agonist
Mechanism of action of GABAPENTIN
GABA analogue ion channel module
Mechanism of action of tizanidine
alpha 1 adrenergic agonist
Namea MS drug that doesn’t work centrally
Dantrolene
2 drugs used as nerve blockers
Botulinum toxin
Intrathecal phenol
Where are active ingredients of cannabis found
Glandular secretions of female cannabis flower
What is the major psychoactive ingredient
THC
What receptor does TBC bind to
CB1 receptor
What kind of receptor is CB1 receptor
G protein coupled receptor
Where is CB1 found
Brain Adipose Tissue Muscle Liver Gi tract Pancreas
Where is CB2 mainly expressed
Immune system
What endrogenous compound binds to CB1
Endocannabinoids such as anandamide and archidonoyl gllycerol
What is the function of the cannabinoid system
To regulate synaptic transmission
What happens if there is too much excitation to glutamate firing neurone
More glutamate fired
Not only binding to glutamate receptors on synaptic cleft, but receptors outside of the cleft
This causes activation of cannaboid
Blocks calcium channels, no calcium entering presynaptic terminal
Modifies over excitation of synapse
How does cannabis affect spasticity
Causes muscle relaxation
What happens in THC is removed from cannabis
No longer working
What happens if you block cannaboid receptors
Makes spasticity worse
Give an example of medical cannabis
Nabiximols
Why isn’t cannabis prescribed in England
Too expensive
What are the pleasant effects of cannabis
High euphoria Relaxation Happiness Sleepiness Disorted perception Slow coordination
Unpleasant effects of cannabis
Appetite enhancement Impaired judgement Hallucinations delusions Psychotic symptoms Reduced motivation
Are street or synthetic cannabis more likely to lead to addiction problems
Synthetic
