Insulin-like Growth Factor 1 (IGF-1) – 010363

IGF-1 is a relatively small peptide (molecular weight 7647) that is tightly bound in serum to one of several high affinity binding proteins.¹ IGF-1 has approximately 50% sequence homology with proinsulin and has a number of biological activities similar to insulin. IGF-1 is a hormone that serves as the major effector of GH-stimulated somatic growth, as well as GH-independent anabolic responses in numerous tissues. IGF-1 has numerous growth-promoting effects, including mitogenic effects and the promotion of cartilage sulfation. Measurement of serum IGF-1 has been widely used in the diagnosis of disorders of GH secretion,^2-6 management of disorders that lead to nutritional insufficiency, or catabolism,^7-9 and monitoring both GH and IGF-1 replacement therapy. IGF-1 measurement may also have a role in the physiology of malignant disease.