Insulin like growth factors and growth hormone deficiency.

polypeptides that act as endocrine mediators of growth hormone (GH)-induced actions. They also function in a paracrine and autocrine manner to regulate cell growth, differentiation, apoptosis and transformation. The IGF system is a complex network comprised of two growth factors (IGF-I and -II), cell surface receptors (IGF-IR and -IIR), high affinity binding proteins (IGFBP), IGFBP proteases as well as several other IGFBP-interacting molecules, which regulate and propagate IGF actions in several tissues(l). The clinical use of measurements of IGF-I has been focused primarily on diagnosing or excluding GH deficiency (GHD) and monitoring GH therapy.