Cell injury and fate Flashcards
The cycle?
Normal cell (homeostasis) –(injurious stimulus)–> cell injury to cell death
normal cell (homeostasis) --(stress, increased demand)--> adaptation --> inability to adapt --> cell injury to cell death
What are the causes of cell injury?
- Oxygen deprivation
- Chemical agents
- Infectious agents
- Immunological reactions
- Genetic defects
- Nutritional imbalances
- Physical agents(injury)
- Aging
What does the cellular response to injurious stimuli depends on?
- the type of injury
- its duration
- its severity
What does the consequence of an injurious stimulus depend on?
- type of cell
- its status
What are the four intracellular systems that are particularly vulnerable?
- cell membrane integrity
- ATP generation,
- protein synthesis
- the integrity of the genetic apparatus
Why do multiple secondary effects rapidly occur?
The structural and biochemical components of a cell are so integrally related that multiple secondary effects rapidly occur.
Cellular function is lost before cell death occurs..
which in turn occurs before the morphological changes are seen
(cardiac- will stop trying to contract whilst alive- if the injury goes on further, they will die)
- just bc a cell looks normal it doesnt mean its functional
What is lethal cell injury?
capable of causing death
What is sublethal cell injury?
consequence of exposure to a chemical or physical process that damages but does not kill a cell
What is morphology?
structural histological changes
What is atrophy?
Shrinkage in the size of the cell (or organ) by the loss of cell substance
What is hypertrophy?
- Increase in the size of cells and consequently an increase in the size of the organ
- Can be physiological (process that occurs in normal healthy people) or pathological (part of the disease process)
What is the cause of hypertrophy?
- increased functional demand
- specific hormonal stimulation
examples of hypertrophy
- uterus during pregnancy (physiological)
- muscle fibres( valve abnormality or hypertension) - pathological
athletes (physiological)
What is hyperplasia?
- increase in the number of cells in an organ
- physiological or pathological