Parsa- Cell injury -2 Flashcards
Cell injury can occur due to abnormalities in:
- Decrease in ATP
- Mitochondrial damage
- Entry of Ca++
- Increase of ROS
- Membrane damage
- Protein misfolding, DNA damage
What are the major causes of ATP depletion
- Reduced supply of oxygen and nutrients
- mitochondrial damage
- action of some toxins
What are drugs that can generate free radicals that are not ROS but have similar effects
- Carbon tetrachloride
2. acetaminophen
Inc intracellular Ca++ causes cell injury by several mechanisms
- In mitochondria it results in opening of the mitochondrial permeability transition pore and failure of ATP generation.
- In cytosol, Inc Ca++ activates a number of enzymes, with deletrious cellular effects.
- intracellular Ca++ results in the induction of apoptosis by direct activation of caspases and by inc mitochondrial permeability
What are the sequence of events in cell injury
- biochemical (funtional)
2. morphologic (structural)
What are features of reversible cell injury
- cellular swelling
- fatty change
- plasma membrane alterations; blebbing, blunting, and loss of microvilli
- dilation of the ER; detachment of polysomes
- mitochondrial changes
- nuclear alterations
What are features of irreversible cell injury
- denaturation of intracellular proteins
- enzymatic digestion of the lethally injured cell.
- Cell contents leak out
- increased esoinphilia
- loss of nuclei
- fragmentation of cells
Hypoxia (reduced oxygen availability)or mitochondrial damage results in inadequate ___ production
ATP
ischemia refers to:
reduced blood flow
what are proteins used in diagnosis of cell damage of cardiac muscle?
- Troponin
2. creatine kinase (MB isoform)
Ischemic injury is associated with _____. Neurons have the shortest endurance for surivival, while ____ have the longest endurance. Transient induction of ____ helps ischemia
inflammation; fibroblasts; hypothermia
Reperfussion can have negative consequences by generation of _____ , influx of neutrophils, and activation of ____ system and promote cell death
ROS; complement
_____ necrosis is a form of necrosis in which the architiecture of dead tissues is preserved for a span of a couple of days. The affected tissues typically exhibit a pale discoloration and firm texture called an _____. Usually occurs in solid organs; the kidney or spleen.
Coagulative; infarct
What enzymes are elevated if hepatocyte cells are damageed
- alanine transaminase (ALT)
2. Aspartate transaminase (AST)
what enzymes are elevated if striated muscle cells are damaged
Creatine kinase (MM isoform)
what enzyme is elevated if exocrine pancreas cells are damaged
Amylase
Release of cytochrome ___ initiates the suicide program of apoptosis. ___ family of proteins regulate apoptosis. This includes the intrinstic/mitochondrial pathway of apoptosis
c; Bcl
TNF receptor, ____ and FADD are included in the ____ pathway of apoptosis
Fas; extrinsic
____ protect damaged proteins from damage
chaperones
_____ remove old/ damaged proteins by acting as a cofactor for proteolysis
ubiquitins