Growth-factor signalling
IGF-1 LR3
What is it?
Long R3 IGF-1 is a modified form of insulin-like growth factor 1, with an N-terminal extension and a substitution in the IGF-1 sequence. It differs from native IGF-1. This attachment explicitly lists LR3; the existing homepage’s generic IGF1 entry is not automatically the same specification.
How it is studied
The modifications reduce affinity for some IGF-binding proteins, changing availability in experimental systems. IGF-related signalling influences cellular growth and metabolism. Altered binding-protein interactions can change experimental responses rather than simply make a compound “better”.
What the evidence shows
Published studies include myogenic-cell experiments and animal work. A guinea-pig infusion study reported changes in organ growth and circulating IGF-related proteins. These findings describe complex biological effects, not evidence of selective muscle gain in people.
Limitations & safety context
Growth-factor activity raises questions about glucose regulation and unintended tissue-growth effects. The LR3 sequence, expression method and possible tags must be confirmed; a published report identified a His-tagged LR3 material in a vial. Neither the generic IGF1 name nor the stated mass verifies identity.
Listed specifications
| Reference | Listed contents |
|---|---|
| IG01 | 100 micrograms |
| IG1 | 1000 micrograms (1 mg) |
Source-document quantities, not doses or a confirmation of stock. Identity, purity, component composition and suitability require separate documentation.
Research information only. No dosing, administration or treatment advice.