GenPath Flashcards
What is the fundamental pathogenesis of cell injury?
A perturbation of homeostasis
Homeostasis refers to the balance and stability of the internal environment of a cell.
What initiates cell injury at the molecular level?
Diverse and numerous specific causes
These causes can vary widely, including physical, chemical, and biological factors.
List the basic mechanisms of cell injury.
- ATP depletion
- Permeabilization of cell membranes
- Disruption of biochemical pathways
- DNA damage
These mechanisms often interact with one another, compounding the effects of cell injury.
What is the consequence of decreased supply of oxygen and nutrients to the cell?
Halts oxidative phosphorylation, leading to rapid ATP depletion
Even cells that can switch to anaerobic glycolysis will experience ATP depletion under these conditions.
What role do mitochondria play in cell injury?
Mitochondria are the major site of ATP generation and are highly vulnerable
Mitochondrial injury can lead to both ATP depletion and increased membrane permeability.
What happens when ATP is depleted in cells?
Causes failure of energy-dependent enzymes
This includes the failure of adenosinetriphosphatase ion pumps that manage cell volume and electrolyte balance.
What are the effects of mitochondrial injury on calcium homeostasis?
Loss of calcium homeostasis and activation of damaging enzymes
These enzymes include phospholipases, proteases, and endonucleases, which can damage various cellular components.
True or False: Membrane damage can occur in isolation without affecting ATP levels.
True
However, in many cases, there is an interplay among mechanisms such as ATP depletion and membrane damage.
Fill in the blank: The failure of _______ leads to cell injury.
[energy-dependent enzymes]
Energy-dependent enzymes are crucial for maintaining cellular functions, and their failure can lead to further damage.
What types of molecules are affected by mitochondrial injury?
- Mitochondrial membranes
- Other cell membranes
- Structural proteins
- Enzymatic proteins
- Nucleic acids
Damage to these molecules can severely impact cell function and viability.
What can cause potentially reversible acute cell swelling to become irreversible?
Severe or persistent injury can overwhelm the cell’s capacity to restore homeostasis.
What are the two types of cell death mentioned?
- Oncotic necrosis
- Apoptosis
How does oncotic necrosis differ from apoptosis?
Oncotic necrosis involves cell swelling, while apoptosis involves cell shrinkage and fragmentation.
What happens if an acutely swollen cell fails to correct electrolyte imbalance?
Potentially reversible cell injury can become the initial stage of oncotic necrosis.
Is oncotic necrosis always unregulated?
No, oncotic necrosis can be a programmed process, similar to apoptosis.
What is necroptosis?
It is a form of programmed cell death that is a type of oncotic necrosis.
What are the stages of programmed cell death?
- Initiation
- Propagation
- Execution
How do cells typically die in oncotic necrosis?
Cells that die by oncotic necrosis tend to do so in groups (foci) or zones.
What is the characteristic feature of apoptosis in terms of cell behavior?
Apoptosis commonly affects individual cells.
What is the result of oncotic necrosis on cell membranes?
Oncotic necrosis results in rupture of cell membranes and release of cell content into the extracellular matrix.
What inflammation response is associated with apoptosis?
Apoptosis elicits minimal inflammation as the fragments remain membrane bound.
Fill in the blank: Programmed cell death has many _______ and intrinsic triggers.
[extrinsic]
What mainly acts through mitochondria in programmed cell death?
Intrinsic triggers.
