Exam 1--Cell Injury Flashcards
Most common cause of cell injury
hypoxia
How does endotoxin lead to shock?
causes changed in blood vessels and coagulation system
2 outcomes of cell overworking/overstimulation?
1) cell adapts and changes
2) becomes exhausted and dies
What determines a cell’s response to an injury? (3 things)
1) type of injury
2) duration of injury
3) severity
what 3 things determine the OUTCOME of cell injury?
1) cell type
2) cell state
3) adaptability of injured cell
5 Most important targets of cell injury
1) aerobic respiration
2) cell membrane integrity
3) protein synthesis
4) cytoskeleton
5) genetic apparatus
T/F: cellular function is lost long before cell death occurs
True
Increases in cytosolic Ca leads to activation of what 4 types of enzymes?
1) ATPases
2) Phospholipases
3) proteases
4) endonucleases
Cell susceptibility to hypoxia:
1) high
2) intermediate
3) low
1) neurons
2) myocardium, heptocytes
3) fibroblasts, skeletal muscle
What are 3 sources of free radicals?
1) absorption of radiant energy
2) normal metabolism
3) enzymatic conversion of chemicals and drugs
2 ways free radicals cause damage
1) lipid peroxidation of membranes
2) oxidation of cellular proteins
Describe lipid peroxidation of membranes
free radicals attack and modify the double bonds in unsaturated fatty acids
Describe oxidation of cellular proteins
free radicals modify the sulfhydral group which results in protein-protein cross linking
How do cysteine and glutathione prevent free radical damage?
enter reactions with free radicals to stabilize them and prevent damage
How does catalase prevent free radical damage
breaks hydrogen peroxide into water and oxygen
What 3 GENERAL things change with necrotic tissue?
Color, strength, and odor
Karyorrhexis vs. Karyolysis
Karyorrhexis–nucleus broken apart and ruptured nuclear envelope
Karyolysis–nuclear chromatin degraded, hollow nuclear membrane
What type of necrosis is grossly firm, dry, and often pale (but can be red/black)
Coagulative
What type of necrosis is associated with LOSS of tissue architecture?
Caseation
What type of necrosis is grossly: dry but greasy, easily crumbles, and is white/grey or yellowish
Caseation
Main cause of caseation necrosis?
Mycobacterial spp.
What are 3 outcomes of caseation necrosis?
encapsulation
mineralization
liquefaction
What makes a cyst different from an abscess?
Cyst is lined by epithelial cells (source of the fluid)
Why does the CNS only undergo liquefactive necrosis?
nervous tissue is high in lipids and low in proteins to coagulate