IGF-1 LR3 vs Ipamorelin
Growth Hormone
IGF-1 LR3
83-amino-acid IGF-1 analog engineered for markedly reduced binding to IGF binding proteins.
Growth Hormone
Ipamorelin
Highly selective pentapeptide ghrelin receptor agonist, notable for minimal cross-activation of other pituitary axes.
Side by side
| Dimension | IGF-1 LR3 | Ipamorelin |
|---|---|---|
| Molecular weight A 12.8× difference in mass — these are not comparable on a milligram-for-milligram basis. | 9117.6 g/mol | 711.85 g/mol |
| Size class | protein-scale | short peptide |
| CAS number | 946870-92-4 | 170851-70-4 |
| Research area | growth hormone | growth hormone |
| Sequence | Not published as a linear sequence | Aib-His-D-2-Nal-D-Phe-Lys-NH2 |
| Available sizes | 1mg | 5mg, 10mg |
| Entry price | $69 | $39 |
| Cost per mg Cost per milligram differs by more than 3×. Compare against the concentrations your protocol actually requires, not the headline vial price. | $69.00 | $4.90 |
Mechanism
IGF-1 LR3
IGF-1 LR3 is a recombinant analog of human IGF-1 carrying two modifications: an arginine substitution at position 3, and a 13-amino-acid N-terminal extension. The Arg3 substitution sharply reduces affinity for IGF binding proteins, which normally sequester the great majority of circulating IGF-1. The practical research consequence is a much larger free fraction and correspondingly extended activity — which also means potency comparisons against native IGF-1 are not straightforward.
Ipamorelin
Ipamorelin is a synthetic pentapeptide agonist at the growth hormone secretagogue receptor (GHS-R1a). Its defining research characteristic is selectivity: unlike earlier secretagogues such as GHRP-6 and GHRP-2, it shows minimal effect on ACTH, cortisol, and prolactin at comparable doses in animal models. That clean profile is precisely why it remains a useful tool compound for isolating GH-axis effects.
Research applications
IGF-1 LR3
- IGF-1 receptor binding and autophosphorylation assays
- IGFBP interaction and displacement studies
- Cell proliferation and differentiation in culture
- Akt/mTOR pathway signaling research
Ipamorelin
- GHS-R1a receptor selectivity and binding studies
- Pituitary somatotroph response assays
- Comparative secretagogue selectivity profiling
- Pulsatile secretion pattern research
Common questions
What is the difference between IGF-1 LR3 and Ipamorelin?
IGF-1 LR3 is 83-amino-acid IGF-1 analog engineered for markedly reduced binding to IGF binding proteins. Ipamorelin is highly selective pentapeptide ghrelin receptor agonist, notable for minimal cross-activation of other pituitary axes. They differ in molecular weight (9117.6 vs 711.85 g/mol) and in the pathways they are studied against.
Which is more cost-effective per milligram, IGF-1 LR3 or Ipamorelin?
Ipamorelin is lower at approximately $4.90 per milligram at its best tier, against $69.00 for the other. Cost per milligram is only meaningful relative to the concentrations a given protocol requires, since these compounds are not used at comparable masses.
Can IGF-1 LR3 and Ipamorelin be studied together?
Combination designs appear in the published literature for a number of these compounds. Whether it is appropriate for a given protocol depends entirely on the model and endpoint. We supply research compounds and do not provide protocol guidance — consult the primary literature for your specific model.
How should IGF-1 LR3 and Ipamorelin be stored?
Store lyophilized at -20°C protected from light. This is a larger protein than most of the catalog and is more sensitive to freeze-thaw; aliquot on first reconstitution. For Ipamorelin: Store lyophilized powder at -20°C protected from light. Reconstituted solution stable at 2-8°C for up to 30 days.
All products are intended strictly for laboratory research use. Not for human or veterinary use. Not for diagnostic or therapeutic use. Not a drug, food, or cosmetic.
Comparison generated from NuVida Vital catalog data. Every specification is reconciled against the certificate of analysis for the shipped batch.