Cell Injury

Front 1

Cellular Adaptation

Back 1

Physiological and pathological response to changes or injury

Front 2

Types of cellular adaptation?

Back 2

Atrophy
Hypertrophy
Hyperplasia
metaplasia

Front 3

Atrophy

Back 3

"Without nourishment"

Shrinkages of Cells
- ultimately shrinkage of organs
- Due to loss of cell substance
Atrophied cells : reduced functional capabilities.

Front 4

Causes of Atrophy

Back 4

Decreased workload
-use it or lose it
Dimished blood or nutrition.
Decreased endocrine stimulation
Loss of nerve supply

Front 5

Hypertrophy

Back 5

Increase in cell size.
Due to synthesis of more cellular component.

Front 6

Hyperplasia

Back 6

Increase in cell number (does not occur in terminally differentiated cells)

Front 7

Potential Causes

Back 7

Potential Causes:
- Physiological
* hormones (e.g., breast and uterus during pregnant)
* compensatory (e.g., liver regeneration)
* would healing.
- Pathological.

Front 8

Metplasia

Back 8

One type of cell changes into another
Pathological process (can be reversible)

Acid reflux - stomach - esophagus junction

Smokers - from columnar epithelium to squamous metaplasia (bronchial epithelium)

Front 9

What causes cell injury?

Back 9

If cells cannot adapt to a stress...

they become injured.

Front 10

Causes of Cell Injury Include:

Back 10

hypoxia
- lack of oxygen required for ATP production
chemicals
infectious agents
- virus, bacteria, parasites, etc.
immune mediated injury
- autoiummune disease
- Genetic diseases
- Physical injury / trauma
e.g., puncture, electrical, radiation, temperature.
-nutritional imbalances
- Aging

Front 11

Hypoxia

Back 11

oxygen deprivation.
common type of injury:

stroke, coronary artery disease

Front 12

Hypoxia is often due to?

Back 12

Ischemia

- decreased blood supply.

Front 13

What is the effective of Hypoxia/Ischemia in regards to sodium/k pump and overall cellular morphology.

Back 13

Acute Swelling - pump dysfunction.

Membrane blebbing - cytoskeleton disruption.

Na pump activity goes down.

Therefore, intracellular concentration of

Ca+ and Na+ will go up leading to cell swelling.

Anaerobic respiration goes up.

Front 14

Irrversible Injuries occur due to

Back 14

excess prolonged exposure to the cell injury.

Front 15

Define Necrosis

Back 15

End product of irreversible cell injury.
Death due to pathology.
-Often influx of immune cells

Front 16

General feature of Necrosis.

Back 16

Cell size is - swelling while apoptotic cell is shrinking
Plasma membrane - is NOT intact while apoptotic cell is intact.
Nuclear change is pyknosis/karyolysis while apoptosis is fragmented.

Front 17

Types of necrosis?

Back 17

Coagulative Necrosis
- injury caused by ischemia or burns.
- The shape and architecture of tissue may intact but cells are dead.

Liquefactive Nercrosis
- inflammatory response gone wild
- Pus formation

Front 18

Intracellular increase in Ca2+ concentration can activate destructive enzymes such as.

Back 18

Phospholipase - damange the cell membrane.

Protease: degrade vital proteins

Endonucleuases: causes DNA degradation.

Front 19

Define reperfusion injury.

Back 19

Reintroduction of blood-flow (oxygen) to cell after modest ischemia that leads to massive cell death.

Front 20

What is the cause of reperfusion injury.

Back 20

Caused by the spike in ROS synthesis with O2.