Cell Injury 8-4-15 Flashcards Preview

MHD > Cell Injury 8-4-15 > Flashcards

Flashcards in Cell Injury 8-4-15 Deck (19):
1

Hyperplasia

number

2

Hypertrophy

increase size

3

Metaplasia

Type switch
-stem

4

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

5

How does loss of energy from hypoxia affect calcium?

increase calcium
-altered membrane permeability and activation of intracellular membranes

6

What does reversible cell injury look like histologically and morphologically ?

histologically:
more pink-eosinophilia

morphology:
-cellular swelling
-steatosis
-myelin figures
-ER swelling
-membrane blebs

7

What does irreversible cell injury look like?

fragmentation and loss of nuclei

8

What is necrosis characterized by?

leukocytes (neutrophils)
-break down of plasma membrane organelles and nucleus; leakage of contents -->inflammatory

-pathologic

9

Coagulation Necrosis
Histology
Macroscopically
Example

severe ischemia of solid organs
Histologically:
-eosinophilia
-ghost-like remnants of intact cells-lack nuclei

Macroscopically:
-tissue firm

Examples:
-Myocardial Infarct
-Renal Infarct

10

Liquefactive Necrosis
Histology
Microscopic
Macroscopically
Example

bacterial infection
Microscopic
-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

***Brain hypoxia

11

Caseous Necrosis
Histologically
Macroscopically

CHEESE
granuloma
Histologically: Amorphous, granular debris (dead cells) in the center of granulomatous cell reaction
Macroscopically: Necrotic tissue is soft, white, friable

12

Enzymatic Fat Necrosis

focal cell death in the pancreas and adjacent fat

Example: acute pancreatitis

13

How does Pancreatitis lead to Enzymatic Fat Necrosis?

lipase-->peripancreatic adipose tissue-->free fatty acids+ calcium

14

Gangrene

Coagulation necrosis of extremity, bowel, gallblader

15

Wet Gangrene

bacteria contaminate dying tissue, superimposing liquefactive necrosis

16

Apoptosis

regulated pattern of cell death
-nuclear condensation and fragmentation
-fragmentation of cytoplasm into apoptotic bodies

-pathologic and physiological
-no inflammation
-removal of dead cell by phagocytes

17

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

18

What happens when ATP is decreased?

decreased intracellular oxygen
-aerobic-->anaerobic
-increased lactic acid-->metabolic acidosis

19

What does ROS lead to? What are some examples?

Lipid peroxidation
Protein modification
DNA damage

Example:
Carbon Tetrachloride-->causes lipid peroxidation, damage to cell structure-dry cleaning

Reperfusion Injury:
-return of blood flow to ischemic tissue-->oxygen derived free radicals--> further injury to cells