Ch. 5 Cellular changes Flashcards
(31 cards)
Atrophy examples (9)
1) broken bone - muscle/bone atrophy
2) post injury/fall - muscle atrophy
3) spinal cord injury - muscle atrophy due to neuromuscular dysfunction
4) bone can atrophy
5) brain tissue can atrophy - cerebral atrophy
6) atrophy of glands
7) vaginal atrophy
8) use of prednisone or steroids can lead to atrophy of adrenal glands
9) steroid use can lead to atrophy of the testes
Hypertophy
Increase in the size of cells due to an increase in functional demand
Results in enlarged tissue mass
Hypertrophy example
Cardiomegaly -> results in less space for blood to flow through the atria and ventricles - severely restrict cardiac output
Hyperplasia
Increase in the number of cells due to an increase in functional demand and/or increased stress
Results in enlarged tissue mass
Hyperplasia- examples
On toes or any place where anything is rubbing on the body
Can lead to calluses of the skin
Gingival Hyperplasia: gums are overriding teeth, side effects of drug use (cyclosporine which is used to treat infection)
Metaplasia
Mature cell type is replaced by a different normal mature cell type, typically due to increased stress
More severe change but is reversible!!
Metaplasia - examples
1) trachea of a smoker -> pseudostratified columnar epithelium is replaced by growth of squamous epithelium
Is reversible if smoker quits !
2) bladder stones can change the epithelium of the bladder
3) GERD can change the epithelium of the esophagus
Dysplasia
Change in cell size, shape, uniformity, arrangement and/or structure typically due to increased stress
Dysplasia - examples
1) pap smears - cervical tissue
Pre-screening for cervical cancer
2) anemia
3) leukemia
Anaplasia
CANCEROUS, NOT REVERSIBLE
Undifferentiated cells with variable nuclear and cell structures
Can imply more advanced cancer
Neoplasm
CANCEROUS, NOT REVERSIBLE
“New growth” - commonly called tumor
Etiologies of cell injury (6)
1) ischemia and hypoxic injury
Loss of blood flow and lack of oxygen
Ischemia can cause more damage
2) free radical injury
3) nutritional injury
4) infectious and immunologic injury
5) chemical injury
6) physical and mechanical injury
First stage of reversible cell injury is:
Hydropic swelling
Hydropic swelling
Cellular swelling due to the accumulation of water
Results from the malfunction of the Na/K pump
If that’s not working, sodium ions will build up in cell and water follows therefore resulting in swelling
Pump fails due to loss of energy or ATP
Will lead to increase in size and weight of that organ
Second stage of reversible cell injury:
Intracellular Accumulations
Mostly reversible
1) normal body substances such as lipids, proteins, melanin can build up in body
2) faulty metabolism (genetic) : ex: tay-sachs disease
3) exogenous products - coal dust enters the lung cells and the lung cannot process the coal dust and so it can build up inside the cell
Free Radical Formation
1) an electrically uncharged atom or group of atoms that contain an unpaired electron
2) unstable, formed by oxidation/reduction process
3) cause damage by:
Lipid peroxidation
Attacks proteins disrupting transporting channels
Irreversible Cell Injury
Necrosis
Necrosis
1) usually occurs as a consequence of ischemia or toxic injury
2) characterized by cell rupture, spilling of contents into extracellular fluid, and inflammation
4 types of necrosis
1) coagulative
2) liquefactive
3) fat
4) caseous
Coagulative Necrosis
A process that begins with ischemia/hypoxia then to loss of energy then to inefficiency of Na/K pump,
Na builds up inside cell, water flows into cell, cell compensates loss of energy through glycolysis to make ATP, byproduct is acid, acid buildup inside cell, cell ruptures, content spills
Liquefactive necrosis
Once cell is damaged and releases its contents, the dead cells start to be dissolved by lysosomal enzymes that are released.
These enzymes can also damage surrounding healthy tissue as well. When this is going on, will form abscesses or cysts from that dissolved dead tissue.
Fat necrosis
Death of adipose tissue mostly due to trauma
Caseous Necrosis
Lung damage secondary to tuberculosis
Consequences of necrosis
1) loss of function
2) inflammatory response (can be localized or systemic) fever, fatigue, malaise, body aches
3) foci of infection
4) release of intracellular proteins
- > serum levels used as markers of cell death
- > troponin levels, myoglobin levels