Atrophy is the partial or complete wasting away of a part of the body. Causes of atrophy include poor nourishment, poor circulation, loss of hormonal support, loss of nerve supply to the target organ, disuse or lack of exercise or disease intrinsic to the tissue itself. Hormonal and nerve inputs that maintain an organ or body part are referred to as trophic.Atrophy is a general physiological process of reabsorption and breakdown of tissues, involving apoptosis on a cell level. When it occurs as a result of disease or loss of trophic support due to other disease, it is termed pathological atrophy, although it can be a part of normal body development and homeostasis as well.
Atrophy examples
In normal development
Examples of atrophy as part of normal development include shrinkage and involution of the thymus in early childhood and the tonsils in adolescence.
Breast atrophy
Atrophy of the breasts can occur with prolonged estrogen reduction, as with anorexia nervosa or menopause