Free IGF-I by analogy with sex and adrenal steroids and thyroid hormones, may be the
major biologically active hormonal form of IGF-I. Because of methodological difficulties in …

Most circulating IGF-I (about 99%) is bound to insulin-like growth factor binding proteins
(IGFBPs), while a very small component (0.5-1%) circulates as a free (= unbound) form (1) …

For nearly 30 years, the endogenous bioactivity of insulin-like growth factor I (IGF-I) has
been estimated by its circulating concentrations of immunoreactive IGF-I, obtained after …

Background: IGF-I immunoassays are primarily used to estimate IGF-I bioactivity. Recently
an IGF-I-specific kinase receptor activation assay (KIRA) has been developed as an …

The objective of the present study was to compare fasting levels of free IGF-I in serum from
patients with adult onset growth hormone deficiency (GHD) and from healthy volunteers, and …

IGF-I is a multipotent growth factor with important actions on normal tissue growth and
regeneration. In addition, IGF-I has been suggested to have beneficial effects on glucose …

During the last decade, there has been an increasing number of publications reporting
concentrations of free dissociable insulin-like growth factor I (IGF-I) in serum or plasma. The …

Insulin-like growth factor I (IGF-I) levels mainly reflect secretion of growth hormone (GH) in
the body. The aims of this study were to compare different IGF-I assay methods in healthy …

While numerous researchers have used rat models to investigate the in vivo actions of IGF-I,
interpretation of the results in terms of true concentrations of rat IGF-I (rIGF-I) in plasma has …

To determine the factors that regulate insulinlike growth factor II (IGF-II), we raised polyclonal
antibodies to this peptide and developed a RIA that measures IGF-II in serum or plasma …