IGF-1 LR3 vs PT-141
IGF-1 LR3 and PT-141 come from different research areas and are studied in largely separate models — researchers usually compare them when scoping a broader protocol.
✓ both US-made · third-party tested · batch COA on every order
at a glance
what each one is
IGF-1 LR3
Recombinant IGF-1 analog polypeptide
IGF-1 LR3 is Long R3 insulin-like growth factor 1, a recombinant analog of human IGF-1 carrying an arginine substitution at position 3 and a 13-residue N-terminal extension. Those two modifications are what define it: they substantially reduce its affinity for the insulin-like growth factor binding proteins (IGFBPs) that sequester native IGF-1 in culture systems.
full IGF-1 LR3 profile →PT-141
Synthetic cyclic heptapeptide melanocortin agonist
PT-141, also known as bremelanotide, is a synthetic cyclic heptapeptide analog of the melanocortin family, structurally related to alpha-melanocyte-stimulating hormone and to the earlier research analog Melanotan II. Verve supplies it as a high-purity research compound for laboratory melanocortin-receptor research.
full PT-141 profile →where the research differs
Both compounds are supplied strictly for laboratory research use only. Reported research contexts for each:
IGF-1 LR3
- IGF-1 receptor binding and signal-transduction research
- PI3K/Akt and MAPK pathway research in cellular models
- Cell-culture media supplementation for proliferation research
- IGFBP interaction and free-ligand availability studies
- Comparative analog research against native IGF-1
PT-141
- Melanocortin-receptor (MC1R/MC3R/MC4R) binding research
- cAMP and G-protein-coupled receptor signaling assays
- Receptor-selectivity and structure–activity profiling
- MC1R and melanogenesis research models in cell culture
- Cyclic-peptide stability and conformation research
shop either compound
Any 2 different compounds take 20% off, any 3 take 30% — applied automatically in the cart, no code. Orders placed Monday–Friday ship by 2pm CT, free over $100.
build a stack with both →frequently asked
What is IGF-1 LR3?
IGF-1 LR3 is Long R3 insulin-like growth factor 1, a recombinant analog of human IGF-1 with an arginine substitution at position 3 and an N-terminal extension. Verve supplies it as a research compound for laboratory use only, not for human or veterinary use.
How does IGF-1 LR3 differ from native IGF-1?
Its structural modifications reduce affinity for IGF binding proteins, so more of the ligand remains unbound in culture systems. Researchers use that property to control free-ligand availability in in-vitro models.
What is PT-141?
PT-141 (bremelanotide) is a synthetic cyclic heptapeptide melanocortin analog structurally related to alpha-MSH. Verve supplies it as a research compound for laboratory use only, not for human or veterinary use.
What is PT-141 studied for in research?
It is used as a reference agonist in melanocortin-receptor research, including MC1R, MC3R, and MC4R binding studies, cAMP signaling assays, and receptor-selectivity profiling. Verve makes no health claims.
related comparisons
verve products are sold for laboratory research and development purposes only and are not intended for human or veterinary use of any kind. statements on this site have not been evaluated by the FDA.