Hormonal

A compound circulating under the names MK-777 and acetamoren is described as a next-generation ghrelin receptor agonist, a successor to MK-677 (ibutamoren). We went looking for the paperwork that would make that description checkable: a primary pharmacology paper, a structure, a patent, a registered trial. We did not find it. What follows is a documented…

A ranking of GH secretagogues — tesamorelin, MK-677, GHRP-2, sermorelin, CJC-1295, ipamorelin — by the quantity and quality of human and regulatory evidence, not efficacy claims.

DES(1-3)IGF-1 is a natural truncated IGF-1 missing three N-terminal residues, giving reduced IGFBP binding, higher in-vitro potency and a short half-life.

Follistatin-344 (FS344) is the follistatin cDNA isoform used in AAV gene-therapy muscle trials. What it binds, how it differs from FS288, and what the data show.

Hexarelin is a synthetic GHRP-family hexapeptide that releases GH via GHS-R1a — and, in rodent hearts, binds CD36. A cited, RUO-only research overview.

GHRP-2 (pralmorelin, KP-102) is a synthetic ghrelin-mimetic GH secretagogue. What the peptide is, how it works, and its Japan-only diagnostic status, examined.

GHRP-6 is the prototype growth hormone-releasing hexapeptide (His-D-Trp-Ala-Trp-D-Phe-Lys-NH2). Its chemistry, GHS-R1a and CD36 pharmacology, and the honest evidence.

A research-use guide to ipamorelin: how it engages the ghrelin receptor (GHS-R1a), why it is described as the first selective GH secretagogue, and an honest read of the animal and limited human data. RUO reference only.

The DAC modification is an elegant piece of chemistry that stretches a peptide’s half-life from minutes to a week. The human evidence behind it is one combined PK/PD trial from 2006. That asymmetry is the whole story.

GRF(1-29) is the rare growth-hormone peptide with a genuine regulatory past — approved, marketed as Geref, then withdrawn for commercial reasons. But its documented history is diagnosis and childhood deficiency, not the longevity claims now attached to it.