Intro to CNS Disorders Flashcards
What is pathogenesis?
the sequence of events from structural changes to clinical manifestations
the development of a health condition
Idiopathic
No known cause
Iatrogenic
Occur as result from medical treatment
Congenital
disease existing at or before birth
Acquired
develops post-fetal
Nosocomial
due to being in hospital environments
Etiology
Definition- the cause
Etiological Agents:
genetic abnormalities
infective agents
chemical
radiation
trauma
malnutrition
Process that underlie pathology
cell injury
inflammation
tissue healing or tissue death
homeostasis
Brain Protection
bones of skull
meninges
blood brain barrier- protects molecules from entering brain
Neurons/Nerve cell
functionally independent of CNS
primary processor of neural signals
neurons don’t divide - THEY CANNOT BECOME TUMORS
Glial Cells (Neuroglia)
typically implicated in disease processes that affect brain tissue
macroglia- astrocytes (provide support) and oligodendrocytes (make myelin)
microglia - immune cells of brain, dormant in absence of infection, scavenger cells that participate in phagocytosis, inflammatory response and immune reactivity
Atrophy Vs. hypertrophy
atrophy- when you break an arm
hypertrophy- when you go to the gym
What is the hallmark of many CNS disorders?
neuronal cell death
Apoptosis
planned or programmed WITHOUT inflammation, normal throughout life
cells shrink, orderly dna fragmentation, caspase activation
ATP required
cell removed by macrophages and no residual damage to CNS
Necrosis
cells swell and explode
disorderly DNA fragmentation
no caspases and no ATP required
WILL be inflammation
necrotic corpse persists
sets off cascade of toxicity
What are the aspects of necrosis that cause the most damage?
inflammation and cascade of toxicity
What causes loss of function from necrosis?
pressure causes the lack of oxygen, leads to cell death
this leaves a scar and scars can’t conduct electricity
Cascade of Toxicity
Ischemia
Release of excess neurotransmitters
Anoxic depolarization
Brain cells unable to produce ATP
Excess influx of Ca due to Ca pump failure
Formation of free radicals
Release of nitrous oxide and cytokines
Continued damage
What is the Fearsome Threesome
NEED TO KNOW
Excitatory amino acids
free radicals
calcium
damaging because of the cascade of toxicity
Etiology of Cell Death
Ischemia/hypoxia
Trauma
Infection
Immune Reaction
Chemical Toxicity
Radiation
Nutritional deficiency
Genetics
How does the brain recover?
Makes new pathways to recover
neural shock resolution
recovery of synaptic effectiveness
recruitment of silent synapses (ones not previously used)
reorganization
Ways to encourage recovery
functionally based movement
motor learning
pharmacology
Factors that affect recovery
age and sex
size of lesion
momentum and appointment (refers to head injury)
environment (nature vs nurture)
training
Medical treatment to CNS issues
pharmacology
surgery
stem cells
