Hypertrophy can be defined as the condition in which the size of the cells increases. As a result of increase in the cell size the corresponding size of the tissue and the organ also increase simultaneously. Here, no increase in cell number occurs.
The increase in cell size is caused by the activation or expression of genes producing proteins responsible for the purpose.
Hypertrophy can be categorized into two types which are as follows:
Physiological Hypertrophy.
Pathological Hypertrophy.
In physiological hypertrophy, the size of the cells increases as a result of growth and development. The process happens sequentially and is regulated spatially and temporally. The growth in cell size and hence the organ comprised of the cells is accompanied by the subsequent growth in all the other structures associated with the organ. An example is the growth in the size of the heart as a child grows into an adult.
In pathological hypertrophy, there is an unregulated, uncontrolled and spontaneous activation of genes producing proteins responsible for causing cell size increase. The increase in cell size cause the subsequent increase in the the size of the organs comprising of the cells but as the process is unregulated no subsequent increase in size of the supportive structures is observed. An example is hypertrophic cardiomyopathy in which the walls of the heart thickens due to growth in size of the cells. This restricts blood flow and causes hypertension.
