What IGF-1 LR300 is, in plain English.
This compound is an 83-amino-acid analogue of IGF-1, insulin-like growth factor 1: the 70-amino-acid growth factor the liver produces in response to growth hormone, and the messenger through which much of growth hormone's action on tissue is carried out. Two changes define it: a 13-residue extension at the N-terminus and an arginine in place of the glutamate at position 3, the 'R3'. Together they stop it binding the IGF-binding proteins that hold natural IGF-1 in circulation and keep most of it inactive. Freed from those proteins it is reported to be about three times as potent as IGF-1 and to last longer in circulation. That is why it stays active far longer in cell-culture work, where it has been a standard laboratory reagent for decades. It is commonly researched for its role in cell growth, protein synthesis and glucose metabolism, and in muscle and tissue-repair models. It is a laboratory reagent and not a medicine: no regulator has approved it for use in people, and the World Anti-Doping Agency prohibits IGF-1 and its analogues in sport. Supplied as 100mcg of freeze-dried powder per vial, the smallest fill in the range, for reconstitution with bacteriostatic water; store at 2–8°C.
