Cell Adaptation + Cell Injury (P) Flashcards
*What are the factors that can cause reversible changes (in cell adaptation)?
1) Size
2) Phenotype
3) Metabolic activity
4) Function cell
What are the types of cell adaptation?
1) Hypertrophy
2) Hyperplasia
3) Atrophy
4) Metaplasia
What is hypertrophy?
It is the increase in cell / tissue size
What is hyperplasia?
It is the increase in cell / tissue #
What is atrophy?
It is the decrease in mass of the cell / tissue
What is metaplasia?
It is the reversible change of 1 type of epithelial adult cells to another type of epithelial adult cells or mesenchymal cells
Why is metaplasia present?
It is present in response to abnormal stimuli
If metaplasia is present, when will the tissue / cell return back to normal?
It returns back to normal when the stimulus is removed
What happens if stimulus persist for a long time (in the case of metaplasia)?
Cancer occurs
What are the types of metaplasia?
1) Epithelial cell metaplasia
2) Mesenchymal cell metaplasia
What is the characteristic of epithelial cell metaplasia?
It is more common > mesenchymal cell metaplasia
What is the characteristic of metaplastic changes present in epithelial cell metaplasia?
These may be patchy or diffused
What is the mechanism present in epithelial cell metaplasia?
The replacement by stronger but less well-specialized epithelium
What are the types of epithelial cell metaplasia?
1) Squamous epithelial metaplasia
2) Columnar epithelial metaplasia
What is the characteristic of squamous epithelial metaplasia?
It is more common > columnar epithelial metaplasia
What is the cause of presence of squamous epithelial metaplasia?
It is present due to chronic irritation
What are the types of chronic irritation that can cause squamous epithelial metaplasia?
1) Mechanical
2) Chemical
3) Infection
Provide ex of the principle of squamous epithelial metaplasia
For habitual smokers, the normal columnar epithelial cells of the trachea and bronchi are replaced by stratified squamous epithelial cells
Where can epithelial cell metaplasia be present and what are the conditions / disorders where epithelial cell metaplasia be present?
1) Prostate gland
2) Chronic prostatitis
3) Estrogen therapy
What is the principle of columnar epithelial metaplasia?
There are some conditions in w/c there’s a transformation of squamous epithelium to columnar epithelium
What are the characteristic of mesenchymal cell metaplasia?
1) It is less often > epithelial cell metaplasia
2) There is a presence of osseus
What is osseus?
It is the formation of bone in fibrous tissue, cartilage, and myxoid tissue
Provide an ex where mesenchymal cell metaplasia is present
In the arterial wall of old people
What are the 4 interrelated cell systems that are vulnerable to injury?
1) Membranes
2) Aerobic respiration
3) Protein synthesis
4) Genetic apparatus
*What are the types of membranes (as a cell system that is vulnerable to injury)?
1) Cellular
2) Organellar
What is the result if the cell is not able to adapt?
It will lead to cell injury
What are the common causes of cell injury?
1) Hypoxia
2) Physical and chemical agents
3) Nutritional deficiency / nutritional imbalances
4) Infections and immunologic causes
5) Iatrogenic causes
6) Genetics
What is the cause of hypoxia?
Reduced blood flow (ischemia)
What are present in the case of hypoxia?
1) Inadequate oxygenation of blood
2) Decrease O2 carrying capacity (anemia)
What are the infections and immunologic causes (w/c are common causes of cell injury)?
1) Hypersensitivity rxns
2) Autoimmune rxns
3) Immune deficiency
Provide an ex of iatrogenic cause (as a common cause of cell injury)?
Accidental ingestion of drugs
What are the genetic causes (w/c are common causes of cell injury)?
1) Inborn errors in metabolism
2) Gross malformations
What are idiopathic diseases?
These are diseases where the cause is not known
What are the basic principles of pathogenesis that remain the same?
1) Nature of injury
2) Duration of injury
3) Severity of the injured cell
4) Type of cell state
5) Adaptability of the injured cell
*The basic principles of pathogenesis w/c remains the same results from what?
These results from various biochemical mechanism acting on several components within the cell
Provide an ex / rationale of pathogenesis
Ischemia (w/c causes hypoxia) is present -> oxidative phosphorylation is decreased -> ATP lvls are decreased
3 results of decreased ATP lvls:
1) Decrease in NA^+ pump -> increase in influx of Ca^2+, H2O, and Na^+ -> increase in efflux of K^+ -> resulting to the swelling of ER and cell, loss of microvilli, and bleb formation
2) Increase anaerobic glycolysis -> 2.1) decrease in glycogen, 2.2) increase in lactic acid, and 3) decrease in pH -> resulting to clumping of nuclear chromatin
3) Detachment of ribosomes is present -> decrease protein synthesis -> resulting to lipid disposition
What are the types of cell injury?
1) Reversible
2) Irreversible
What is the principle of reversible cell injury?
If the injury (cell / tissue) can regain homeostasis and return to its morphologically and functionally normal state
What is the principle of irreversible cell injury?
It the injury (cell / tissue) can’t be brought back to its normal lvl, even if the cell injury stimulus is removed
What is the result if irreversible cell injury is present?
It results to cell death
