Compensatory_growth_(organ)
Compensatory growth (organ)
Type of regenerative growth
Compensatory growth is a type of regenerative growth that can take place in a number of human organs after the organs are either damaged, removed, or cease to function.[1] Additionally, increased functional demand can also stimulate this growth in tissues and organs.[2] The growth can be a result of increased cell size (compensatory hypertrophy) or an increase in cell division (compensatory hyperplasia) or both.[3] For instance, if one kidney is surgically removed, the cells of the other kidney divide at an increased rate.[1] Eventually, the remaining kidney can grow until its mass approaches the combined mass of two kidneys.[1] Along with the kidneys, compensatory growth has also been characterized in a number of other tissues and organs including:
- the adrenal glands[4][5]
- the heart[5][6]
- muscles[5]
- the liver[5][7]
- the lungs[8]
- the pancreas (beta cells and acinar cells)[7]
- the mammary gland[5]
- the spleen (where bone marrow and lymphatic tissue undergo compensatory hypertrophy and assumes the spleen function during spleen injury)[5]
- the testicles[5]
- the thyroid gland[5][9]
- the turbinates[medical citation needed]
A large number of growth factors and hormones are involved with compensatory growth, but the exact mechanism is not fully understood and probably varies between different organs.[1] Nevertheless, angiogenic growth factors which control the growth of blood vessels are particularly important because blood flow significantly determines the maximum growth of an organ.[1]
Compensatory growth may also refer to the accelerated growth following a period of slowed growth, particularly as a result of nutrient deprivation.