LeRoith D, McGuinness M, Shemer J, Stannard B, Lanau F, Faria T N, Kato H, Werner H, Adamo M, Roberts C T
Diabetes Branch, NIH, Bethesda, MD 20892.
Biol Signals. 1992 Jul-Aug;1(4):173-81. doi: 10.1159/000109323.
The insulin-like growth factors (IGF-I and IGF-II) play important roles in the regulation of growth and metabolism. While the liver is the main source of circulating IGFs, their production by numerous extrahepatic tissues suggests the existence of autocrine and paracrine modes of action in addition to typical endocrine mechanisms. The actions of the IGFs are mediated through their activation of specific cell surface receptors, primarily the IGF-I receptor, although some effects may be mediated through the IGF-II receptor and the insulin receptor. The stability of the IGFs and their interaction with their receptors are mediated by specific IGF binding proteins (IGF-BPs) which are found in the circulation and in extracellular fluids. Thus, the overall biological actions of the IGFs can be regulated by control of ligand biosynthesis, modulation of receptor levels and postreceptor signalling pathways, and changes in the levels and activity of IGF-BPs.
胰岛素样生长因子（IGF-I和IGF-II）在生长和代谢调节中发挥着重要作用。虽然肝脏是循环中IGF的主要来源，但许多肝外组织也能产生IGF，这表明除了典型的内分泌机制外，还存在自分泌和旁分泌作用模式。IGF的作用是通过激活特定的细胞表面受体介导的，主要是IGF-I受体，不过有些效应可能是通过IGF-II受体和胰岛素受体介导的。IGF的稳定性及其与受体的相互作用由特定的IGF结合蛋白（IGF-BP）介导，这些蛋白存在于循环和细胞外液中。因此，IGF的整体生物学作用可通过控制配体生物合成、调节受体水平和受体后信号通路，以及改变IGF-BP的水平和活性来调节。
