This is the chain that carries growth signals. The hypothalamus prompts the pituitary, the pituitary releases growth hormone in bursts, and growth hormone prompts the liver and other tissues to make IGF-1, which stands for insulin-like growth factor 1. IGF-1 carries out much of the downstream work and then signals back to damp the chain down. Growth hormone arrives in pulses, mostly at night, while IGF-1 stays comparatively steady across the day.

Why it matters here

Because IGF-1 is steady and growth hormone is not, the two do not track each other from hour to hour, and a measurement of one is not a measurement of the other. A compound described as acting on this axis is acting somewhere along the relay, which need not be on growth hormone itself.

Also called

• gh / igf-1 axis
• gh/igf-1 axis
• gh igf-1 axis
• gh-igf-1 axis
• growth hormone axis
• gh axis
• gh
• igf-1
• igf1
• insulin-like growth factor 1
• somatotropin
• somatomedin c

GH is growth hormone, also called somatotropin. IGF-1 was formerly known as somatomedin C, and the insulin-like part of its name refers to its shape resembling insulin, not to it acting as insulin.

Compounds carrying this term

None on file yet. This term is in the controlled vocabulary but no compound record currently uses it — which is a statement about our coverage, not about the term.

See also

• Pituitary gland — Body and drug basics
• Hypothalamus — Body and drug basics
• HPA axis — Body and drug basics
• Endogenous vs exogenous — Body and drug basics