What is
GLP-5?

A fragment of substance P

Substance P is an endogenous messenger of eleven amino acids, formed from the precursor protein protachykinin-1 (gene TAC1). It belongs to the tachykinin family and is the preferred binding partner of the neurokinin-1 receptor.

GLP-5 is not the whole molecule but its tail end: residues 5 to 11, that is seven amino acids. Because the section by which substance P binds to its receptor sits at the end of the molecule, this fragment remains active at the receptor. It also arises in the body itself — dipeptidyl peptidase IV degrades substance P to precisely this fragment via intermediate steps.

Where the name comes from — and why it can mislead

“Glp” stands for pyroglutamate, the amino acid at position 5. In IUPAC-IUB nomenclature, pyroglutamic acid (5-oxoproline) carries the symbol Glp; other suppliers therefore list the same substance as [Pyr5]-Substance P (5-11). Both mean the same residue.

“Glp” here does not stand for “glucagon-like peptide”. That is the most common confusion, and an understandable one: GLP-1 is the messenger from which medicines such as semaglutide are derived. GLP-5 has nothing to do with it — on four independent levels:

• Different origin. Substance P comes from the gene TAC1, GLP-1 from proglucagon.
• Different family. Tachykinins here, glucagon-like peptides there.
• Different size. Seven amino acids against roughly thirty.
• Different receptor. Neurokinin-1 against the GLP-1 receptor.

Nor is there a “GLP series” in which GLP-5 follows GLP-1. Proglucagon gives rise to GLP-1 and GLP-2 — nothing more. The 5 in our trade name denotes the position in the molecule, not a generation.

What the substance has been studied for

The fields below describe what others have done with this and related fragments. They are not a statement about what the substance does in a human being.

• Receptor pharmacology. Shortened variants of substance P serve to determine which part of the molecule actually activates the neurokinin-1 receptor.
• Neuropharmacology. A widely cited paper by Khan and co-workers (1995) examined dopamine release in rat brain slices.
• Radiopharmacy. The fragment has been used as a docking piece to neurokinin-1 receptors on glioma cell lines.
• Metabolism of substance P. As a naturally occurring degradation product, the fragment is itself a subject of study.

A note on accuracy that we consider important: some of the work cited was carried out with the unmodified fragment Substance P (5-11) (CAS 51165-09-4), not with the pyroglutamate form we supply. The two compounds differ by a ring closure at the front end. Anyone drawing on the literature should check this.

What it is not intended for

GLP-5 is a laboratory chemical. It is not a medicine, not a food supplement and not a cosmetic. It has been tested neither for sterility nor for tolerability, holds no medicines authorisation, and must not be applied to humans or animals.

We make no statements about what the substance does in a human being — there are no robust data on this, and such statements would not be permissible for a product of this kind. If you arrived here from a search for weight-loss products: this substance is not intended, not studied and not suitable for that purpose. The details are set out in the restriction on use.

What you receive from us

Lyophilisate in a multi-dose vial, 20 mg net weight, type I clear glass with a crimp cap. Every batch comes with a certificate of analysis including an HPLC chromatogram and mass spectrum — available before you order. Purity is determined for each batch individually and is ≥ 99 % by RP-HPLC at 220 nm.