Disclaimer
CompoundIQ publishes research summaries for informational and educational purposes only. Nothing on this site constitutes medical advice, diagnosis, or treatment recommendations. Always consult a licensed healthcare provider. Many compounds listed are research chemicals not approved for human use.
IGF-1 LR3
Also known as: Long R3 IGF-1, Long Arginine 3-IGF-1, Insulin-like Growth Factor 1 Long R3
IGF-1 LR3 is a modified form of insulin-like growth factor 1 with an arginine substitution at position 3 and a 13-amino-acid N-terminal extension, giving it a significantly longer half-life than native IGF-1. It has reduced binding affinity for IGF binding proteins, resulting in greater bioavailability and potency. It is a powerful anabolic agent used in research for muscle hypertrophy and cell proliferation.
Risk Level
High RiskDifficulty
Advanced| CAS Number | 946870-92-4 |
| Class | Peptide |
| Category | Well-Known Peptides |
Mechanism of Action
IGF-1 LR3 binds to the IGF-1 receptor, activating the PI3K/Akt and MAPK/ERK signaling pathways that drive protein synthesis, cell proliferation, and inhibition of apoptosis. Its structural modifications reduce binding to IGFBPs by over 95%, keeping it in its free, active form much longer than endogenous IGF-1. It promotes satellite cell activation and muscle hyperplasia in addition to hypertrophy, and has potent glucose-lowering effects similar to insulin.
Dosing Research
Research doses typically range from 20-100 mcg/day administered subcutaneously or intramuscularly. Cycles are generally limited to 4-6 weeks due to receptor desensitization concerns. Bilateral site injections into target muscle groups are sometimes employed.
Side Effects & Risks
Hypoglycemia is a significant risk due to insulin-like activity and requires careful glucose monitoring. Potential to promote growth of existing tumors or precancerous cells is a serious concern. Other side effects include joint pain, jaw pain, organ growth with prolonged use, and gut distension. Acromegalic-like symptoms may occur with chronic administration.
Research Studies
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Disclaimer
CompoundIQ publishes research summaries for informational and educational purposes only. Nothing on this site constitutes medical advice, diagnosis, or treatment recommendations. Always consult a licensed healthcare provider. Many compounds listed are research chemicals not approved for human use.