IGF-1 LR3
IGF-1 LR3 is not a peptide. It is indexed alongside Growth factors and growth hormone-derived compounds because it appears in the same research literature and the same search demand; no statement on this site describes it as a peptide.
Identity
| Field | Value |
|---|---|
| Classification | Not a peptide |
| Primary class | Growth factors and growth hormone-derived compounds |
| CAS registry number | Unknown PubChem returned no compound record for this name on the retrieval date, so this field is not sourced. |
| PubChem CID | Unknown PubChem returned no compound record for this name on the retrieval date, so this field is not sourced. |
| UniProt accession | Unknown No UniProt query was run in v1. |
| Molecular formula | Unknown PubChem returned no compound record for this name on the retrieval date, so this field is not sourced. |
| Molecular weight | Unknown PubChem returned no compound record for this name on the retrieval date, so this field is not sourced. |
| Amino-acid sequence | Unknown Not reported by the PubChem property set retrieved for this record; no sequence database query was run in v1. |
| Reported half-life | Unknown No pharmacokinetics source was retrieved in v1. PubChem does not carry half-life as a property, so this is recorded as not yet sourced rather than estimated. |
What the cited literature examines
IGF-1 LR3, reported in the literature as Long R3 IGF-I, is a modified form of insulin-like growth factor I. It is an 83-residue protein rather than a short peptide, and PubChem returned no compound record for the name, so the identity fields on this page are unsourced rather than estimated. The retrieved records are animal and cell-culture work. A 1997 American Journal of Physiology paper reports that the somatotropic axis in neonatal calves can be modulated by nutrition, growth hormone and Long R3 IGF-I.
A 2004 Journal of Cellular Physiology paper reports the effect of recombinant porcine IGFBP-3 on IGF-I and Long R3 IGF-I stimulated proliferation and differentiation of L6 myogenic cells, a 2005 Journal of Endocrinology paper reports production of recombinant porcine IGF-binding protein-5 and its effect on porcine embryonic myoblast cultures, and a 2008 Journal of Endocrinology paper reports lactation performance in the mouse under growth hormone and Long R3 IGF-I.
[2, 3, 4, 5]Reported mechanism
A modified insulin-like growth factor I; the retrieved records study it as an IGF-I analogue with reduced binding to IGF-binding proteins in myogenic cell and animal models.
[3, 4]Taken from the cited 2004 Journal of Cellular Physiology and 2005 Journal of Endocrinology titles, which examine it alongside IGF-binding proteins.
Targets named in the cited records: IGF-1 receptor, IGF-binding proteins.
FDA application register
A query of the FDA Drugs@FDA application register on 2026-10-09 returned no application records for this compound name. This compound is not approved by the FDA for human use.[1]
Scope statement: this records the result of a single automated query against the openFDA drugsfda endpoint on the stated date. It is not legal advice and is not a jurisdiction-by-jurisdiction legality assessment.
Retrieved 2026-10-09.
Amounts reported in the cited literature
Unknown. No retrieved record in this dataset states an amount, so none is shown. Where an amount is recorded it is what a named study reported administering in its own stated model, in the past tense, and is not a protocol.
No study-reported dose was taken from a source read in v1. Literature-reported values are only recorded where the retrieved citation metadata states the figure.
Adverse effects reported in the cited literature
Unknown. No retrieved record in this dataset reports an adverse effect for this compound, so no row is shown. Absence of a row records the absence of a retrieved report, nothing more.
No adverse-effect row was taken from a source read in v1. Rows are only recorded with the study model named and the reporting citation attached.
Other names
IGF-1 LR3 appears under these other names in the cited records or in common usage. Each one resolves to this page rather than to a separate page of its own.
- Long R3 IGF-I
- LR3-IGF-I
- long arginine 3 IGF-1
Where this page sits
Research records
Cited research records for IGF-1 LR3, each with its identifier, the publication type it is indexed as, and the study model stated by its assigned subject headings.
Compounds indexed next to it
- IGF-1 DES — Growth factors and growth hormone-derived compounds
- Mechano growth factor — Growth factors and growth hormone-derived compounds
- Somatropin — Growth factors and growth hormone-derived compounds
Class page: Growth factors and growth hormone-derived compounds. Full index: all indexed compounds.
Questions this page answers
What does the cited literature examine for IGF-1 LR3?
IGF-1 LR3, reported in the literature as Long R3 IGF-I, is a modified form of insulin-like growth factor I. It is an 83-residue protein rather than a short peptide, and PubChem returned no compound record for the name, so the identity fields on this page are unsourced rather than estimated.
Which class is IGF-1 LR3 indexed under?
IGF-1 LR3 is indexed under Growth factors and growth hormone-derived compounds. This class groups the growth factors, growth factor fragments and growth hormone-derived proteins that research-peptide catalogues list alongside the secretagogues, most of which are proteins rather than peptides and are labelled as such on their pages.
What does the FDA application register show for IGF-1 LR3?
A query of the FDA Drugs@FDA application register on 2026-10-09 returned no application records for this compound name. This compound is not approved by the FDA for human use.
Sources
- Drugs@FDA application register query for this compound, no application records returned. U.S. Food and Drug Administration, openFDA drugsfda endpoint (2026). fda:igf-1-lr3
- The somatotropic axis in neonatal calves can be modulated by nutrition, growth hormone, and Long-R3-IGF-I. The American journal of physiology (1997). pmid:9252489
- Effect of recombinant porcine IGFBP-3 on IGF-I and long-R3-IGF-I-stimulated proliferation and differentiation of L6 myogenic cells. Journal of cellular physiology (2004). pmid:15254966
- Production of recombinant porcine IGF-binding protein-5 and its effect on proliferation of porcine embryonic myoblast cultures in the presence and absence of IGF-I and Long-R3-IGF-I. The Journal of endocrinology (2005). pmid:15817840
- Enhancement of maternal lactation performance during prolonged lactation in the mouse by mouse GH and long-R3-IGF-I is linked to changes in mammary signaling and gene expression. The Journal of endocrinology (2008). pmid:18577570
On each stated value was matched to the record cited for it. That is record matching, not an appraisal of the research. Compiled and checked by: Peptide Monographs editorial desk. No qualified clinical reviewer.