Merck, I3769-50UG, Insulin-like Growth Factor-I human

General description
Insulin-like growth factor I (IGF-I) is localized on human chromosome 12q23.2.
Application
Insulin-like Growth Factor-I human has been used:
in modified Dulbecco minimal essential medium for in vitro culture of testicular cells
in culture media, to study its effect on steroidogenesis during testicular development
in culture media for in vitro assay of splenic pro-erythroid cell growth and differentiation

Biochem/physiol Actions
IGF-I also known as somatomedin C, is secreted from the liver into circulation in a process regulated by pituitary growth hormone (GH) and so it mediates the growth-promoting activity of GH. In the developing embryo IGF-I is expressed primarily by mesenchymal-derived cells. After birth IGF-I expression in most extrahepatic tissues declines and hepatic expression of IGF-I becomes GH-regulated. Expression of IGF-I outside the liver is regulated differently, depending on the specific tissues. For example, gonadotropins and sex steroids regulate IGF-I expression within the reproductive system, while parathyroid hormone and sex steroids regulate IGF-I expression in bone. IGF-I is produced in several human tumors. IGF-I is mitogenic for a variety of cells including fibroblasts, osteoblasts, smooth muscle cells, fetal brain cells, neuroglial cells, and erythroid progenitor cells. IGF-I exerts its actions exclusively through the IGF-I receptor (IGF-IR). IGF-I induces endothelial cell migration and is involved in the regulation of angiogenesis.
IGF-I, also known as somatomedin C, mediates the growth-promoting activity of GH (growth hormone). IGF-I induces endothelial cell migration and is involved in the regulation of angiogenesis. IGF-I exerts its actions through the IGF-I receptor.
Insulin-like growth factor I (IGF-I) plays a critical role in cellular energy metabolism and growth and development, especially prenatal growth.
Physical form
Lyophilized from 0.2 μm filtered solution in 50 mM acetic acid.
Preparation Note
Reconstitute in water
Analysis Note
The biological activiy is calculated by the dose-dependent proliferation of murine BALBC/3T3 cells. ED50 corresponds to a specific activity of at least 1 x 105 units/mg.