AHK, also referred to as Tripeptide-3, is a short oligopeptide composed of the amino acids alanine, histidine, and lysine. In laboratory research, AHK is utilized as a molecular probe to study peptide-mediated regulation of fibroblast activity, extracellular matrix (ECM) dynamics, and endothelial-associated signaling pathways in preclinical experimental systems.

Sequence (Three-Letter Code): Ala-His-Lys
Molecular formula: C15H26N6O4
Molecular weight: 354.41 g/mol

The histidine residue within the AHK sequence provides a metal-coordination site, which enables reversible complexation with copper ions in experimental settings. This property has made AHK a frequent subject of structure–function studies examining how short peptides interact with metal cofactors and influence downstream biochemical behavior.

• Fibroblast activation studies: Examination of peptide-driven changes in fibroblast proliferation and ECM-related gene expression.

• Extracellular matrix research: Investigation of collagen and elastin synthesis pathways in cultured connective tissue cells.

• Endothelial signaling: Analysis of vascular endothelial growth factor (VEGF)–associated pathways in cellular and animal models.

• Growth factor modulation: Studies focused on transforming growth factor beta-1 (TGF-β1) regulation and its role in connective tissue biology.

• Peptide–metal interaction research: Use of AHK as a reference peptide in copper coordination and redox-related biochemical experiments.

Fibroblasts are central regulators of connective tissue architecture through their production of ECM proteins, including collagen and elastin. These cells also secrete signaling molecules that influence endothelial behavior and vascular development. Endothelial cells, in turn, participate in angiogenic and maintenance programs governed by growth factor signaling networks.

Mechanistic studies have examined AHK-mediated modulation of VEGF-linked signaling cascades and TGF-β1–associated transcriptional programs. These pathways are commonly studied in preclinical systems to understand how short peptides influence fibroblast–endothelial cross-talk and ECM remodeling under controlled laboratory conditions.

In vitro and animal-model studies have evaluated AHK as a regulator of fibroblast-associated ECM synthesis. In cultured dermal fibroblasts, exposure to AHK has been associated with increased collagen type I expression under specific experimental conditions, supporting its use as a mechanistic probe in collagen-related research [1].

Additional preclinical investigations have explored AHK-driven modulation of angiogenesis-related signaling, including effects on endothelial growth factor expression and vascular-associated cellular responses in experimental hair follicle models [2,3]. These studies are frequently cited to contextualize AHK within broader connective tissue and vascular biology research frameworks.

AHK (Tripeptide-3) is supplied as a purified research reagent intended for laboratory experimentation. Product identity and purity are typically confirmed using analytical techniques such as high-performance liquid chromatography (HPLC) and mass spectrometry (MS). Standard peptide handling and storage practices should be followed in research environments.

1. neova-dna-nourishing-study.pdf. Available at: http://www.dermacaredirect.co.uk/skin/frontend/default/dermacare/pdf/neova-dna-nourishing-study.pdf. (Accessed: 25th July 2016)
2. Pyo, H. K. et al. The effect of tripeptide-copper complex on human hair growth in vitro. Arch. Pharm. Res. 30, 834–839 (2007).
3. Pollard, J. D., Quan, S., Kang, T. & Koch, R. J. Effects of copper tripeptide on the growth and expression of growth factors by normal and irradiated fibroblasts. Arch. Facial Plast. Surg. 7, 27–31 (2005).

ALL ARTICLES AND PRODUCT INFORMATION PROVIDED ON THIS WEBSITE ARE FOR INFORMATIONAL AND EDUCATIONAL PURPOSES ONLY.

The products offered on this website are furnished for in-vitro studies only. In-vitro studies (Latin: in glass) are performed outside of the body. These products are not medicines or drugs and have not been approved by the FDA to prevent, treat or cure any medical condition, ailment or disease. Bodily introduction of any kind into humans or animals is strictly forbidden by law.

For Laboratory Research Only. Not for human use, medical use, diagnostic use, or veterinary use.