Confronto
IGF-1 LR3 vs. Ipamorelin
Due peptidi a confronto — identità, base di evidenze, stato legale ed eventi avversi noti.
Identità
Categoria
Crescita
Crescita
N. CAS
143045-27-6
170851-70-4
Peso molecolare
9117.6 g/mol
711.86 g/mol
Emivita
21 h
2 h
Sequenza
MFPAMPLSSLFVNGPRTLCGAELVDALQFVCGDRGFYFNKPTGYGSSSRRAPQTGIVDECCFRSCDLRRLEMYCAPLKPAKSAAib-His-D-2-Nal-D-Phe-Lys-NH2Meccanismo d'azione
IGF-1 LR3
IGF-1 LR3 is a recombinantly produced variant of human IGF-1. Two changes define its properties: (1) at position 3, glutamic acid is replaced by arginine; (2) a 13-amino-acid sequence is added at the N-terminus ('Long'). Both modifications drastically reduce affinity for the six IGF-binding proteins (IGFBP-1 to -6) that normally bind native IGF-1 in the blood and regulate its availability at the receptor. As a result, a larger fraction of the molecule is freely available to bind the type-1 IGF receptor (IGF-1R) — the same receptor as native IGF-1. In preclinical models and cell culture, LR3 IGF-1 therefore acts as a more potent agonist than unmodified IGF-1. The downstream signalling pathway (PI3K/Akt and MAPK) is identical to that of IGF-1; the modification changes bioavailability, not the receptor target.
Ipamorelin
Ipamorelin is a selective agonist at the GH secretagogue receptor (GHSR-1a). Compared to GHRP-2 and GHRP-6 its selectivity for the growth-hormone axis is higher; ACTH, cortisol and prolactin are not significantly stimulated in clinical studies. This selectivity was the main reason for its development over older GHRPs.
Base di evidenze
Evidenza più alta
Modello animale
RCT sull'uomo
Studi
4
4
di cui sull'uomo
0
3
Effetti registrati
4
3
Contraddizioni aperte
1
1
Eventi avversi documentati
1
1
Stato legale
Voci complete
Frequently asked questions
- What is the difference between IGF-1 LR3 and Ipamorelin?
- IGF-1 LR3 is classified as "Crescita", while Ipamorelin is classified as "Crescita". IGF-1 LR3: Synthetic analogue of insulin-like growth factor 1 (IGF-1) carrying an arginine substitution at position 3 and a 13-amino-acid N-terminal extension. These modifications lower binding to IGF-binding proteins and extend its duration of action relative to native IGF-1. LR3 IGF-1 is primarily an established cell-culture reagent (serum-free media, bioprocessing); it is NOT an approved human medicine. Use in the bodybuilding grey market is described; as an IGF-1 analogue, LR3 IGF-1 falls under the WADA anti-doping prohibition. Ipamorelin: Synthetic pentapeptide and selective growth-hormone secretagogue. Developed at Novo Nordisk in the 1990s as a pentapeptide GHRP successor; clinical development was discontinued after phase 2 (post-operative ileus). This page contrasts both neutrally and source-based — with no usage or dosing recommendation.
- Which peptide is better supported by science, IGF-1 LR3 or Ipamorelin?
- The highest available evidence level is "Modello animale" for IGF-1 LR3 and "RCT sull'uomo" for Ipamorelin. A higher evidence level means more robust data, but says nothing about suitability for an individual. The full body of evidence is on each peptide's own page.
- What is the legal status of IGF-1 LR3 and Ipamorelin in Germany and the United States?
- Germania: IGF-1 LR3 — Non approvato, Ipamorelin — Non approvato. Stati Uniti: IGF-1 LR3 — Non approvato, Ipamorelin — Non approvato. These are factual summaries with source and review date on the individual pages.