Lecture 3 Cellular Injury Flashcards
Dynamic steady state
Body maintains itself at a relatively constant composition
Cell injury
Occurs when cells are exposed to severe stress that no longer allows them to maintain homeostasis which results in structural and functional changes
Cells injury vs cell death
Cell injury is reversible but cell death is irreversible
Basic changes that occur in cell injury
1) dysfunction of NA+/K+ pump
2) loss of plasma membrane integrity 3) defects in protein synthesis ability
4) intracellular accumulations
5) genetic damage
Hypoxia
Deficiency of oxygen
Hypoxemia
Deficiency of oxygen in blood
Ischemia
Local reduction of blood flow (oxygen)
Cyanosis
Bluish coloration of the skin and mucous membrane caused by hypoxia
Infarction
An area of dead tissue to an organ caused by lack of blood flow in that area
Nercrosis
Death of a small area of tissue or part of an organ that is surrounded by healthy tissue
Gangrene
Death of a large portion of tissue
Eschar
Blackened, thick layer of necrotic tissue often seen in Burns and decubiti
Prolonged ischemia
Susceptible to infarction
Causes of death of tissue
- genetic replication errors
- nutritional deficiencies (high LDL)
- Chemical agents
- free radicals
- Physical injuries
- hypoxia
Free radical injuries
Free electron that attracts and attached to membrane and damage them
Highly reactive molecules made by the body during inefficient mitochondrial metabolism
