Cell Injury And Fate Flashcards
Cause of cell injury
O2 deprivation
Chemical agent
Infectious agent
Immunological reaction
Genetic defect
Nutritional imbalance
Physical agent
Ageing
What intracellular system would become vulnerable
Cell membrane integrity
ATP generation
Protein synthesis
Genetic apparats integrity
What is atrophy and e.g.
Shrinkage in size of cell.
I.e dementia- brain.
Muscle atrophy/denervation.
What is hypertrophy and examples
Increase in size of cell.
Physiological: uterus during pregnancy.
Pathological: myocyte adaption to increase load.
What is Hyperplasia and examples
Increase in NUMBER of cells.
Physiological: proliferation endometrium.
Pathological: carcinoma
What is metaplasia and examples
REVERSIBLE changes in which one cell tripe is replaced by another.
Physiological: pregnancy- cervix: columnar epithelium-> SQUAMOUS. Pregnancy ends: cervix- back to columnar.
Same for smokers
Another example of metaplasia apart from pregnancy
Barrett’s oesophagus: squamous epithelium -> COLUMNAR -> squamous.
People with acid reflux.
What is dysplasia and examples
Precancerous cells. Show malignancy. But NOT invading underlying tissue.
Nucleus size increases
Barrett’s oesophagus
What are microscopic changes associated with reversible injury
Fatty change- alcohol
Cellular swelling- ballooning degeneration
What is necrosis
Cell death from inflammation
4 light microscopic changes associated with IRREVERSIBLE injury
Coagulative necrosis
Liquefaction necrosis
Caseous necrosis
Fat necrosis
What is coagulative necrosis and examples
Tissue dead but shape/structure maintained.
Myocardial infarct
What is liquefactive necrosis and examples
Becomes liquid.
Old cerebral infarct
What is caseous necrosis and examples
Cheesy
Pulmonary TB
Something related to kidney with granular look
What is fat necrosis and example
Acute pancreatitis- enzyme leak. Lipase digest fat on pancreas -> free fatty acid + Ca2+ -> precipitate/calcium salt.
Cause of apoptosis
Embryogenesis.
Deletion of auto-reactive T cells in thymus.
Cell deletion in proliferating population.
Injures
Difference between apoptosis and necrosis
A may be physiological.
A needs ATP.
A not associated with inflammation.
How does necrosis happen
Enzymatic digestion and leakage of cellular contents out of membrane- cause inflammation
How apoptosis happen
Phagocytosis of apoptosis cells and fragments (contained within cell membrane). Controlled/programmed cell death
What is Necroptosis
Combo of apoptosis+necrosis.
Programmed cell death with inflammation.
One cause: viral infection. Energy dependent.
