Dictionary Definition
atrophy
Noun
1 a decrease in size of an organ caused by
disease or disuse [syn: wasting, wasting
away]
2 any weakening or degeneration (especially
through lack of use) [syn: withering] v : undergo
atrophy; "Muscles that are not used will atrophy" [also: atrophied]
User Contributed Dictionary
English
Etymology
From French atrophie < atrophia < (atrophia) “a wasting away” < (atrophos) “ill-fed, un-nourished” < (a-) “not” + (trophē) “nourishment” < (trephō) “I fatten.”Pronunciation
- /ˈæ.trə.fi/
- /"
Extensive Definition
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 cellular
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 atrophies
Atrophy of the breasts can occur with prolonged estrogen reduction, as with anorexia nervosa or menopause. Atrophy of the testes occurs with prolonged use of enough exogenous sex steroid (either androgen or estrogen) to reduce gonadotropin secretion. The adrenal glands atrophy during prolonged use of exogenous glucocorticoids like prednisone.Muscle atrophies
Disuse atrophy of muscles (muscle
atrophy) and bones,
with loss of mass and strength, can occur after prolonged
immobility, such as extended bedrest, or having a body part
in a cast (living in darkness for the eye, bedridden for the legs
etc.). This type of atrophy can usually be reversed with exercise
unless severe. Astronauts must exercise regularly to minimize
atrophy of their limb muscles while they are in
microgravity.
There are many diseases and
conditions which cause atrophy of muscle mass. For example diseases
such as cancer and AIDS induce a body wasting syndrome called
"cachexia", which is
notable for the severe muscle
atrophy seen. Other syndromes or conditions which can induce
skeletal muscle
atrophy are congestive
heart failure and liver disease.
During aging, there is a
gradual decrease in the ability to maintain skeletal muscle
function and mass. This condition is called "sarcopenia", and may be
distinct from atrophy in its pathophysiology. While the exact cause
of sarcopenia is unknown, it may be induced by a combination of a
gradual failure in the "satellite
cells" which help to regenerate skeletal muscle fibers, and a
decrease in sensitivity to or the availability of critical secreted
growth factors which are necessary to maintain muscle mass and
satellite cell survival.
Dystrophies, myosities, and motor neuron conditions
Pathologic atrophy of muscles
can occur due to diseases of the motor nerves, or due to diseases
of the muscle tissue itself. Examples of atrophying nerve diseases
include CMT (Charcot Marie Tooth syndrome) poliomyelitis,
amyotrophic lateral sclerosis (ALS or Lou Gehrig's disease),
and Guillain-Barre
syndrome. Examples of atrophying muscle diseases include
muscular
dystrophy, myotonia
congenita, and myotonic
dystrophy.
Vaginal atrophies
In post-menopausal women, the
walls of the vagina atrophy and become thinner. The mechanism for
the age-related condition is not yet clear, though there are
theories that the effect is caused by decreases in estrogen
levels.
Research
It has been reported that Astemizole might prevent 97% of the muscle wasting that occurs in immobile, bedridden patients. Testing upon mice showed that it blocked the activity of a protein present in the muscle that is involved in muscle atrophy. However the concerns for the drug's longterm effects on the heart preclude its routine use in humans for this indication and further alternative drugs are being sought.References
atrophy in Bulgarian:
Атрофия
atrophy in Danish:
Atrofi
atrophy in German:
Atrophie
atrophy in Spanish:
Atrofia
atrophy in Esperanto:
Atrofio
atrophy in French:
Atrophie
atrophy in Italian:
Atrofia
atrophy in Lithuanian:
Atrofija
atrophy in Dutch:
Atrofie
atrophy in Japanese:
萎縮
atrophy in Norwegian:
Atrofi
atrophy in Polish:
Atrofia
atrophy in Portuguese:
Atrofia
atrophy in Russian:
Атрофия
atrophy in Swedish:
Atrofi
atrophy in Ukrainian:
Атрофія
Synonyms, Antonyms and Related Words
Sanforizing, abnormality, abscess, acute disease, affection, affliction, ague, ailment, allergic disease,
allergy, anemia, ankylosis, anoxia, apnea, asphyxiation, asthma, ataxia, attenuation, backache, bacterial disease,
birth defect, bleeding,
blennorhea, blight, cachexia, cachexy, cardiovascular disease,
chill, chills, chronic disease,
circulatory disease, colic, complaint, complication, condition, congenital defect,
constipation,
consume, consume away,
consumption,
convulsion, coughing, cyanosis, decadence, declension, declination, decline, defect, deficiency disease,
deformity, degeneracy, degeneration, degenerative
disease, devolution,
diarrhea, disability, disease, disorder, distemper, dizziness, downfall, downgrade, dribble away,
dropsy, drying, drying up, dysentery, dyspepsia, dyspnea, edema, emaceration, emaciate, emaciation, endemic, endemic disease,
endocrine disease, epidemic disease, fainting, fatigue, fever, fibrillation, flux, functional disease, fungus
disease, gastrointestinal disease, genetic disease, growth, handicap, hemorrhage, hereditary
disease, high blood pressure, hydrops, hypertension, hypotension, iatrogenic
disease, icterus,
illness, indigestion, indisposition, infectious
disease, infirmity,
inflammation,
insomnia, itching, jaundice, labored breathing,
low blood pressure, lumbago, malady, malaise, marasmus, marcescence, morbidity, morbus, muscular disease, nasal
discharge, nausea,
necrosis, neurological
disease, nutritional disease, occupational disease, organic
disease, pain, pandemic
disease, paralysis,
parching, pathological
condition, pathology,
pine away, plant disease, preshrinkage, protozoan
disease, pruritus,
psychosomatic disease, rash, respiratory disease, rheum, rockiness, run to seed, run to
waste, sclerosis,
searing, secondary
disease, seediness,
seizure, shock, shrinkage, shrinking, shriveling, sickishness, sickness, signs, skin eruption, sneezing, sore, spasm, symptomatology, symptomology, symptoms, syndrome, tabes, tachycardia, the pip,
thinning, tumor, upset stomach, urogenital
disease, vertigo, virus
disease, vomiting,
wastage, waste, waste away, wasting, wasting disease,
wilting, wither away,
withering, worm
disease