Lecture 1: Cell Injury Flashcards
(87 cards)
__ is an abnormal body process with a characteristic set of signs or symptoms and lesions that may affect the whole body or any of its parts.
Disease
The fundamental disease process begins with injury at the __ level
molecular and cellular
__ refers to damage or pathologic alterations in cell molecules or structure
cell injury
__ are cell alterations that are associated with disease
lesions
What are the 8 causes of cell injury
- hypoxia/hypoxemia
- physical agents
- chemicals/drugs
- infectious agents
- immunologic reactions
- Genetic defects
- nutritional imbalances
- aging
What are the responses to cell injury
- adaptation (hypertrophy)
- reversible cell injury
- irreversible cell injury and death (necrosis and apoptosis)
Necrosis (oncotic necrosis) is a pattern of cell death that often follows hypoxic, toxic and microbial injury and is characterized by __
Cell swelling with nuclear changes
__ is cell death induced by tightly regulated intracellular program where enzymes degrade the cell’s nuclear DNA and proteins leading to nuclear framentation w/o loss of plasma membrane integrity
Apoptosis
3 microscopically visible changes in reversible cell injury
- cell swelling
- chromatin clumping
- lipidosis
7 ultrastructural changes in reversible cell injury
- dilation of ER
- ribosomal detach from RER
- Loss of microvilli and cilia
- mitochondrial swelling
- chromatin clumping
- membrane blebs
- lipid accumulation
Many things that cause swelling are due to
mitochondrial damage
Ischemia causes a decrease in oxidative phosphorylation by the mitochondria which causes a decrease in __
ATP
Decrease in ATP due to ischemia causes what 3 things
- decrease Na pump (ER, cellular swell, loss of microvilli, blebs)
- increase anaerobic glycolysis
- decreased protein synthesis
What happens when ischemia causes decreased ATP leading to decreased Na pump activity
Ca, water, and Na flow into the cell and K flows out causing swelling
What happens when ischemia causes decreased ATP leading to an increase in anaerobic glycolysis
cell uses up glycogen (decreases) and pH decreases (acidic) causing chromatin clumping
When ischemia causes decreased ATP and protein synthesis what can be seen
lipid deposition
Irreversible cell injury (necrosis) has 2 microscopically visible changes
- nuclear changes (pyknosis, karyorrhexis, chromatolysis)
2. increased eosinophilia of cytoplasm
Irreversible cell injury (necrosis) has 4 ultrastructural changes
- high mitochondrial swelling
- membrane defects
- lysosomal membrane rupture
- nuclear condensation, fragmentation, dissolution
Necrotic tissue has what gross changes
pale/dull coloration
what are the 6 forms of necrosis discussed
- coagulation necrosis (simplest)
- liquefactive necrosis
- caseous necrosis
- gangrenous necrosis
- fat necrosis
- fibrinoid necrosis
What are 3 microscopic features seen in coagulative necrosis
- nuclear changes
- increased eosinophilia of cytoplasm
- cell borders STILL VISIBLE
__ necrosis pathogenesis is due to high influx of neutrophils (protease destruction) in tissue with high fat content (brain, lung)
liquefactive
Liquefactive necrosis has 3 microscopic features
- LOSS of cell borders (unlike in coagulative necrosis)
- granular basophilic and eosinophilic debris with nuclear fragments
- tissue structure is obliterated
__ necrosis involves recruitment of macrophages with persistence of stimulus and inflammatory cell component breakdown and is commonly seen in mycrobacterial infections
caseous