Research Comparison
IGF-1 LR3 vs Ipamorelin
A side-by-side research comparison of IGF-1 LR3 and Ipamorelin drawn from DRPSHP' peptide database records.
IGF-1 LR3
IGF-1 LR3 is insulin-like growth factor 1 altered in two ways, and the name is a record of both: L for the long N-terminal extension of 13 amino acids added to native IGF-1's 70, giving 83 residues in total, and R3 for arginine replacing glutamate at position 3. Together these changes reduce its affinity for the IGF-binding proteins that normally hold most IGF-1 in bound complexes. It is made by recombinant methods and is best known as a supplement in serum-free media for growing mammalian cell lines. Beyond cell culture the published work is chiefly animal studies, with very limited human data.
Ipamorelin
What made Ipamorelin interesting in its original animal pharmacology was what it did not do. Older growth hormone-releasing peptides raised ACTH and cortisol alongside growth hormone; in those studies this one did not, and that selectivity is the reason it is still discussed. It is a synthetic pentapeptide, Aib-His-D-2-Nal-D-Phe-Lys-NH2, derived from the earlier compounds in the class and a residue shorter than both GHRP-2 and GHRP-6, acting as an agonist at the ghrelin receptor GHS-R1a. Because that receptor also sits in the gut, rodent models of gastrointestinal motility have used it as well. A small number of human clinical studies exist; the bulk of what is known is animal work, and human data remain limited.
Reading a comparison
A comparison places two records side by side; it does not merge them. Each description above is drawn from that compound's own record, and the two were not necessarily characterised by the same methods, at the same time, or to the same level of detail. Before comparing any attribute, it is worth establishing that both records describe the substance you think they describe — names are not identifiers, and two entries sharing a name can differ in salt form, stereochemistry or the convention used to state a mass. Where a figure carries no method beside it, the comparison is between two reported numbers rather than between two measurements.