IGF-1 LR3 (Long R3 IGF-1) is a modified form of insulin-like growth factor-1 with two key modifications: an arginine (R) substitution at position 3 and a 13-amino acid N-terminal extension peptide. These modifications dramatically reduce binding to IGF binding proteins (IGFBPs), resulting in a much longer half-life (20-30 hours vs 12-15 minutes for native IGF-1) and greater bioavailability. IGF-1 LR3 is approximately 2-3 times more potent than regular IGF-1 in stimulating protein synthesis and cellular growth. It is widely used in cell culture to support cell proliferation and is popular in muscle growth research due to its extended activity and systemic effects.
Key Data
Mechanism of Action
Binds IGF-1 receptor with reduced affinity for binding proteins, increasing bioavailability and half-life.
Reported Benefits
All information is presented for Research Use Only (RUO). Not medical advice.