GLP-2-T is a research-market listing label for tirzepatide, a synthetic 39-residue peptide studied as a dual agonist at the glucose-dependent insulinotropic polypeptide (GIP) receptor and the glucagon-like peptide-1 (GLP-1) receptor. Cowboy Chems lists it as GLP-2(T) with the molecular formula C₂₂₅H₃₄₈N₄₈O₆₈, a molecular weight of 4813.5 g/mol, and CAS number 2023788-19-2. The label is a catalog convention, not a chemical name. The "2" refers to two receptors, and the "T" identifies tirzepatide. The compound is unrelated to glucagon-like peptide-2, the intestinal hormone that shares the GLP-2 name, and that collision is the source of most of the confusion behind searches for "what is GLP 2-T." The compound is supplied lyophilized for laboratory research only.
Why is tirzepatide called GLP-2 when GLP-2 is a different hormone?
The research market adopted a numbering series to sort incretin-class compounds by how many receptors they engage: GLP-1 for the semaglutide-class single agonists, GLP-2 for the tirzepatide dual agonist, and GLP-3 for the retatrutide triple agonist. The series is convenient for catalogs and wrong as pharmacology, because the proglucagon gene already encodes a real hormone called GLP-2. Native GLP-2 is a 33-residue peptide co-secreted with GLP-1 from intestinal L-cells, acting at its own receptor (GLP-2R) on intestinal epithelium, and its clinical analog is teduglutide. Tirzepatide does not bind GLP-2R and has no structural relationship to GLP-2. A researcher who searches the literature for "GLP-2" will find intestinal epithelial biology; a researcher who searches a vendor catalog for "GLP-2" will find tirzepatide. The retatrutide research overview covers the GLP-3 step of the same series.
What is the structure of GLP-2-T (tirzepatide)?
Tirzepatide is a 39-amino-acid single-chain peptide built on a GIP backbone rather than a GLP-1 backbone, with the sequence Tyr-Aib-Glu-Gly-Thr-Phe-Thr-Ser-Asp-Tyr-Ser-Ile-Aib-Leu-Asp-Lys-Ile-Ala-Gln-Lys-Ala-Phe-Val-Gln-Trp-Leu-Ile-Ala-Gly-Gly-Pro-Ser-Ser-Gly-Ala-Pro-Pro-Pro-Ser. Three design features define it. Alpha-aminoisobutyric acid (Aib) at positions 2 and 13 blocks cleavage by dipeptidyl peptidase-4, which otherwise inactivates native incretins within minutes. A C20 fatty di-acid moiety is attached through a linker to the lysine at position 20, driving reversible albumin binding and the multi-day half-life reported in pharmacokinetic studies. And the C-terminal region carries a proline-rich extension derived from exendin-4 that contributes to stability. The GIP-derived N-terminus is what gives the molecule its GIP receptor activity; substitutions in the mid-region are what add GLP-1 receptor engagement.
What receptors does GLP-2-T act on?
Published pharmacology characterizes tirzepatide as an agonist at two class B G-protein-coupled receptors, the GIP receptor and the GLP-1 receptor, both signaling predominantly through Gs and cyclic AMP in pancreatic beta cells and other target tissues. In vitro characterization by the developing group reported the compound's affinity at the GIP receptor as comparable to native GIP, and its affinity at the GLP-1 receptor as several-fold lower than native GLP-1, with a bias toward cAMP signaling over beta-arrestin recruitment at the GLP-1 receptor. That imbalanced profile was deliberate and is the reason tirzepatide is studied as a distinct compound rather than as a GLP-1 analog with extra activity. Cowboy Chems' GLP-1 and DPP-4 degradation article covers the enzymatic stability problem the Aib substitutions solve.
How does GLP-2-T differ from GLP-1(S) and GLP-3(R)?
The three market-label compounds share a design logic and differ in receptor count and backbone. Semaglutide (GLP-1(S)) is a 31-residue GLP-1 backbone with a C18 fatty di-acid at lysine 26, a single agonist at 4113.6 g/mol. Tirzepatide (GLP-2(T)) is a 39-residue GIP backbone with a C20 fatty di-acid at lysine 20, a dual agonist at 4813.5 g/mol. Retatrutide (GLP-3(R)) adds glucagon receptor activity to GIP and GLP-1 engagement, a triple agonist at 4731.3 g/mol. The molecular weights do not increase monotonically with receptor count, because tirzepatide's longer C-terminal extension outweighs retatrutide's additional receptor-engaging substitutions. Molecular weight and CAS number are the identifiers that resolve any of the three from a listing; the labels are not reliable across vendors, and some list tirzepatide as GLP-1(T) rather than GLP-2(T).
What does the T in GLP-2-T stand for?
The T stands for tirzepatide. As with the R in GLP-3(R) for retatrutide and the S in GLP-1(S) for semaglutide, the suffix was added to disambiguate as more compounds entered each numbered tier. Listings written as GLP-2T, GLP-2(T), GLP-2 T, and GLP-2-T all refer to the same molecule when the CAS number matches 2023788-19-2. A listing under any GLP-2 label with a molecular weight near 4,813 Da is tirzepatide. A listing with a weight near 3,900 Da (the mass of native GLP-2) or one describing intestinal epithelial activity is the real hormone or its analog teduglutide, and is a different compound entirely.
How should researchers verify a GLP-2-T listing?
Three checks resolve it. The CAS number should read 2023788-19-2. The molecular weight should be stated near 4813.5 g/mol with the formula C₂₂₅H₃₄₈N₄₈O₆₈; the formula itself is a frequent search term because it is the fastest way to confirm identity across vendors. And the Certificate of Analysis should report an observed mass from mass spectrometry matching that theoretical value, since HPLC purity alone confirms cleanliness rather than identity. The third-party testing explainer and the COA limitations article cover what each test does and does not establish.
What is GLP-2-T studied for in research?
Tirzepatide is studied in pancreatic beta-cell, adipocyte, and hepatocyte models for concurrent GIP and GLP-1 receptor signal transduction, receptor internalization and recycling, cAMP kinetics, and signaling bias. The clinical program registered under the developer's code produced the SURPASS and SURMOUNT trial series, which are the source of the published human pharmacology data, and the compound is an approved pharmaceutical product in several jurisdictions under its own brand names. That regulatory status applies to the pharmaceutical product and its manufacturer, not to research-grade material. The research-market compound sold under the GLP-2-T label is intended for in vitro characterization of receptor pharmacology, stability, and analytical profile.
All compounds referenced in this article, including GLP-2(T) (tirzepatide), are supplied for research purposes only and are not for human use. Nothing here describes or endorses any use outside laboratory research. These products are not intended to diagnose, treat, cure, or prevent any disease.
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