Synonyms: growth hormone, somatotrophin
Related tests: IGF-I, Insulin
Clinical significance
GH is a hormone of the anterior pituitary gland whose production is controlled by the hypothalamus: it is stimulated by SRF (somatotrophin-releasing factor) and inhibited by SIF (somatotrophin-inhibiting factor). GH stimulates protein synthesis by promoting the uptake of amino acids by cells and their incorporation into proteins, and therefore body growth. GH acts through peptides collectively called somatomedins, produced by the liver under the influence of GH itself. Some somatomedins (IGF-I and IGF-II) have an insulin-like action.
Clinical indications
Dwarfism, acromegaly
Sample type
The patient must have a blood sample taken.
Preparation
You must fast for at least 8 hours; a small amount of water is allowed. Before the blood test the patient must rest (seated) for at least half an hour.