growth hormone

Hormone from the anterior pituitary gland that promotes growth of long bones and increases protein synthesis.

If it is lacking in childhood, dwarfism results; excess GH causes gigantism.

Levels of GH are high in the fetus and decline throughout early childhood; there is another spurt at adolescence and then production declines throughout adulthood. After the age of about 60 only tiny amounts of GH are produced, and this ‘deficiency’ is responsible for some of the symptoms of aging.

Growth hormone release is controlled by growth hormone releasing hormone (GHRH) and the peptide somatostatin, both produced in the hypothalamus.

The American Association of Clinical Endocrinologists estimated in September 1998 that only two-fifths of growth hormone sold in the USA is used legitimately, to treat children with a deficiency. Other uses include abuse by sports people to improve physique and by others in the belief that it will delay ageing. Risks of growth hormone abuse include heart disease and problems with bone growth.