The relationship between normal, adapted, reversibly injured, and dead

myocardial cells.

Tissue Normal Metaplasia Stimulus

AirwaysPseudo stratified

columnar epitheliumSquamous epithelium Cigarette smoke

Urinary bladderTransitional

epitheliumSquamous epithelium Bladder stone

Oesophagus Squamous epithelium Columnar epithelium

Gastro- esophageal

reflux (Barrett's

Oesophagus)

Cervix Glandular epithelium Squamous epithelium Low pH of vagina

Influx of calcium: activation of enzymes that damage cellular components and may also trigger apoptosis

Intra cellular accumulations

a) A normal substance is produced at a normal or an increased rate, but the

metabolic rate is inadequate to remove it. An example of this type of process is

fatty change in the liver.

b) A normal or an abnormal endogenous substance accumulates because of

genetic or acquired defects in its folding, packaging, transport, or secretion.

Mutations that cause defective folding and transport may lead to accumulation of

proteins.

c) An inherited defect in an enzyme may result in failure to degrade a metabolite. The

resulting disorders are called storage diseases.

d) An abnormal exogenous substance is deposited and accumulates because the cell has neither the enzymatic machinery to degrade the substance nor the ability

to transport it to other sites. Accumulations of carbon or silica particles are

examples of this type of alteration

Intra cellular

accumulations

Fatty Change (Steatosis).

Cholesterol and Cholesteryl Esters

Proteins

Glycogen

Pigments

Cell Injury& Necrosis

Ischemic and Hypoxic

Injury

Ischemia-Reperfusion

Injury

Chemical (Toxic) Injury