IGFS AND THEIR BINDING-PROTEINS

Insulin-like growth factors (IGFs), initially known as somatomedins, e nd their specific, high-affinity binding proteins (IGFBPs) are synthes ized in most tissues, but principally in the liver. The interest of me asuring their circulating levels, which reflect liver production, is t o obtain indications as to their endocrine function and regulation. IG F-I plays a pivotal role in post-natal growth. its half-life is signif icantly increased by its association with IGFBPs and its serum levels reflect somatotropic status, unlike growth hormone (GH) which has a mu ch shorter half-life and whose secretion comes in pulses. Since invest igation of growth retardation must include the most finely tuned appre ciation possible of somatotropic secretion, assays of IFG-I and electr ophoretic analysis of IGFBP profile can be useful tools, both diagnost ically and therapeutically, and can help in determining the need or ot herwise for GH treatment, especially in view of the growing demand for such therapy.