HGH Fragment 176-191
Also known as HGH Frag 176-191, AOD fragment, GH fragment 176-191, Frag 176-191
HGH Fragment 176-191 is a 16-residue C-terminal piece of the growth-hormone molecule, studied in lipid-metabolism contexts rather than as a GH secretagogue. A profile of a genuinely different mechanism.
HGH Fragment 176-191 is the odd one out in this group, and the difference is worth stating up front. Every other compound here works upstream — telling the pituitary to release growth hormone, whether as a GHRH analog or a ghrelin mimetic. This one is not a signal to release anything. It is a piece cut from the growth-hormone molecule itself, corresponding to the tail end of the protein.
That distinction reframes everything about how it is studied. This page stays descriptive — its identity as a fragment, the research context it appears in, and its relationship to AOD-9604 — without dosing or outcome claims.
A synthetic 16-residue peptide corresponding to the C-terminal region (residues 176 to 191) of the human growth-hormone molecule. It is a fragment OF the hormone itself — not a releasing peptide and not a secretagogue — which makes its mechanism of study fundamentally different from the rest of this cluster. It is closely related to the modified fragment AOD-9604.
A fragment of the hormone, not a releaser
Human growth hormone is a 191-amino-acid protein. HGH Fragment 176-191 reproduces just its final 16 residues — the C-terminal region. Because it is a synthetic slice of the hormone rather than a molecule that acts on the GHRH or ghrelin receptors, it does not belong to either the GHRH-analog or the secretagogue branch. It sits in its own category within the growth-hormone family.
The research interest in this particular region is that it has been associated in the literature with the fat-metabolism (lipolytic) portion of growth-hormone activity, studied separately from the hormone's growth-promoting effects. That is a research context — where the fragment has been examined — not a promised outcome.
Relationship to AOD-9604
HGH Fragment 176-191 is the parent structure behind AOD-9604, which is essentially the same C-terminal fragment with a stabilizing modification added. The two are frequently discussed together for exactly that reason, and comparing them is a common way to understand what the modification in AOD-9604 is meant to change.
Grouping the fragment with AOD-9604 also underscores the point that both are studied in metabolic and lipid contexts, distinct from the pituitary-signaling research that defines the GHRPs and GHRH analogs.
These are research areas the compound is associated with in the literature — not medical claims or intended uses.
Handling & storage
Supplied lyophilized. Stored sealed and cold; reconstituted with bacteriostatic water only as a protocol requires, then refrigerated. Handle per accepted laboratory practice.
Verify a certificate by lot →Common questions
No. Unlike the GHRPs and GHRH analogs, it does not signal the pituitary to release growth hormone. It is a synthetic fragment of the growth-hormone molecule itself, corresponding to residues 176-191.
AOD-9604 is essentially the same C-terminal fragment with a stabilizing modification. HGH Fragment 176-191 is the parent structure, and the two are often studied side by side.
It has been studied in relation to the lipid-metabolism (lipolytic) portion of growth-hormone activity, distinct from growth-promoting effects. This describes where it has been examined, not a claimed result.
This monograph is a research-use reference. It describes composition and the contexts in which the compound has been studied — it is not medical advice, a description of effects, or a recommendation for use. Sold strictly for laboratory and research use; not for human or animal consumption.