Hypertrophy is an increase in the size of individual cells. In multicellular organisms, growth is typically achieved through a combination of this cellular enlargement and hyperplasia, which is an increase in the number of cells. While distinct processes, they often occur concurrently. Hypertrophy can lead to a relative increase in the volume of a tissue or organ, and contributes to the overall growth of an organism. In organisms characterized by eutely, where the total number of somatic cells is fixed upon reaching maturity, post-embryonic growth is achieved almost exclusively through hypertrophy. In humans and other mammals, hypertrophy is a normal physiological process, such as the hormonally induced enlargement of uterine cells during pregnancy.

Clinical significance in humans

Eccentric hypertrophy is a type of hypertrophy in which the walls and chamber of a hollow organ undergo growth, resulting in an overall increase in size and volume. It is most commonly described in the left ventricle of the heart. Sarcomeres are added in series, as for example in dilated cardiomyopathy (in contrast to hypertrophic cardiomyopathy, a type of concentric hypertrophy, where sarcomeres are added in parallel).

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Gould Pyle 234.jpg|Breasts

Hypertrophied clitoris.jpg|Clitoris

Head of a boy with hypertrophy of the ear Wellcome L0062496.jpg|Ear

Gould Pyle 127.jpg|Fingers

Feet from a case of partial hypertrophy of the foot Wellcome L0061374.jpg|Foot (partial)

Hypertrophy of the gums Wellcome L0062728.jpg|Gums

Hypertrophy from Carswell, 1838. Wellcome L0000931.jpg|Heart

Kidney hypertrophy Wellcome L0005308.jpg|Kidneys

Face of man with hypertrophy of the temporal muscles Wellcome L0062508.jpg|Temporal muscles

Tibia affected by chronic inflammatory hypertrophy Wellcome L0061256.jpg|Tibia (inflammatory)

Inflammatory hypertrophy of the tongue Wellcome L0061277.jpg|Tongue (inflammatory)

Gould Pyle 100.jpg|Upper lip

Operative gynecology - (1906) (14780430391).jpg|Urethral meatus

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See also

  • Athlete's heart
  • Ventricular hypertrophy (including left ventricular hypertrophy and right ventricular hypertrophy)
  • Muscle hypertrophy
  • List of biological development disorders

References

  • University of California Muscle Physiology Home Page: Hypertrophy