Cell Adaptations: pathology:HYPERTROPHY HYPERPLASIA AND METAPLASIA

A series of video tutorials discussing the pathology of cell injury and adaptations.
In this tutorial , i have discussed Hypertrophy, Hyperplasia and Metaplasia.
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HYPERTROPHY
Increase in the SIZE of the parenchymal cells
increase in the size of the organ
Cause :
Increased functional demand or
Stimulation by hormones and growth factors
Mechanisms :
Increased production of cellular proteins.
Due to the increased activation of genes responsible for the production of these proteins
sometimes a subcellular organelle may undergo selective hypertrophy
Eg: patients on barbiturates show hypertrophy of the smooth endoplamic reticulum (ER) in hepatocytes.

HYPERPLASIA
Increase in the NUMBER of cells in an organ
It takes place if the cell population is capable of dividing
Mechanism :
Results from growth factor induced proliferation of mature cells or
Increased output of new cells from stem cells.

METAPLASIA
It is a reversible change
in which one differentiated cell type (epithelial or mesenchymal) is replaced by another cell type
Mechanism
Due to REPROGRAMMING of the precursor cells, present in the normal tissues.
Differentiation into a new cell lineage
By signals generated by various cytokines, growth factors, and extracellular matrix components in the cells' environment.

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Please watch: "WARBURG EFFECT: Hallmark of CANCER. What, Why & How?"
   • NEOPLASIA 6: WARBURG EFFECT: Hallmark of  ...  
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