insulinlike growth factors
(IGF) serum peptides with insulin-like actions, formerly called somatomedins (q.v.). IGF-I (formerly somatomedin C) is an important growth hormone–dependent mediator of cell growth and replication. IGF-II (formerly somatomedin A) appears to be essential for normal embryonic development and may play special roles in the central nervous system. Both are similar in sequence and structure to proinsulin.
Medical dictionary.
2011.