Flashcards in Cell Injury 8-4-15 Deck (19)
Hypoxia leads to...
1. decrease oxidative phosphorylation
2. decrease in ATP
a. decrease Na pump--->increase in Na and water in cell--> swelling
b. increase in anerobic glycolysis -->glycogen, increase lactic acid, Decreased PH--->clumping of nuclear chromatin
c. Detachment of ribosomes-->decrease protein synthesis-->lipid deposition
How does loss of energy from hypoxia affect calcium?
-altered membrane permeability and activation of intracellular membranes
What does reversible cell injury look like histologically and morphologically ?
What does irreversible cell injury look like?
fragmentation and loss of nuclei
What is necrosis characterized by?
-break down of plasma membrane organelles and nucleus; leakage of contents -->inflammatory
severe ischemia of solid organs
-ghost-like remnants of intact cells-lack nuclei
-bacteria release enzymes causing a rapid loss of cellular structure and a collection of liquid
Macroscopic: creamy yellow material
-abscess=collection of neutrophils, dead cells, liquid
Histologically: Amorphous, granular debris (dead cells) in the center of granulomatous cell reaction
Macroscopically: Necrotic tissue is soft, white, friable
Enzymatic Fat Necrosis
focal cell death in the pancreas and adjacent fat
Example: acute pancreatitis
How does Pancreatitis lead to Enzymatic Fat Necrosis?
lipase-->peripancreatic adipose tissue-->free fatty acids+ calcium
Coagulation necrosis of extremity, bowel, gallblader
bacteria contaminate dying tissue, superimposing liquefactive necrosis
regulated pattern of cell death
-nuclear condensation and fragmentation
-fragmentation of cytoplasm into apoptotic bodies
-pathologic and physiological
-removal of dead cell by phagocytes
What are the principle mechanisms of cell injury?
1. Mitochondria--> decrease ATP & increase ROS
2. Increase Cellular Calcium-->increase mito permeability & activation of enzymes
3. Integrity of Membranes
4. Integrity of Genetic Material, Protein misfolding
What happens when ATP is decreased?
decreased intracellular oxygen
-increased lactic acid-->metabolic acidosis