Atrophy

The atrophy or atrophy ( to ancient Greek: ἀτροφία, Modern Greek: ατροφία, nlat.: atrophia = " leaning ", " exhaustion ", " lack of food ", " stunting ") means tissue shrinking. It can occur by volume or decrease in size of the cells ( so-called simple atrophy) or by a decrease in cell number ( numerical atrophy = hypoplasia) with or without concurrent changes in cell structure. The opposite of atrophy is a hypertrophy or hyperplasia. A growth depression is compared with the standard reduced growth. You can have all the reasons that can also cause atrophy.

In contrast to the atrophy hypoplasia means a reduced system of an organ, such as the testis.

Atrophy can occur, inter alia, for the following reasons:

• Due to malnutrition,
• Due to a metabolic disorder
• Due to an infectious, physical or chemical injury,
• Because of a failure of the blood supply,
• Due to a disturbance of innervation,
• Due to hormonal changes, such as a lack of growth hormones or growth factors,
• As a symptom of old age,
• From overloading, for example, by muscle stress without proper rest,
• Due to mechanical pressure ( pressure atrophy ), for example, by: the pressure of a tumor or a poorly fitting prosthesis and / or
• Under therapy with glucocorticoids.
• Because of excessive alcohol consumption

Already a underuse of an organ leads to disuse atrophy, such as the muscle and bone loss in a lack of physical activity or in space ( due to lack of gravity). In addition, some institutions show a physiological atrophy (also known as involution ), such as the thymus, which regresses during puberty.

Atrophy may occur either in general ( universal atrophy, for example in malnutrition ) or to specific organs within an organ or tissue is limited.