Kisspeptin
Research Guide

What is kisspeptin?

Kisspeptin is the common name for a family of peptides. They are cut from the protein made by the KISS1 gene. The gene was first described in melanoma cells as a metastasis suppressor. It was named KiSS-1 (Lee et al., 1996). Five years later, three groups found that its product is cut into peptides. These peptides activate the orphan receptor GPR54, now called KISS1R. One is a 54-residue peptide named metastin (Ohtaki et al., 2001).

The others are shorter C-terminal fragments of 14, 13 and 10 residues. They bind the receptor with low nanomolar affinity (Kotani et al., 2001; Muir et al., 2001). The material sold as kisspeptin for lab work is normally kisspeptin-10. This is the C-terminal decapeptide. It is also written KP-10 or metastin (45-54). Disguised Alpha supplies it as a lyophilized powder for laboratory research use only. Nothing on this page is guidance for use in people.

Kisspeptin reference data

Formula, molecular weight, CAS number and size come from the kisspeptin product page. Sequence and aliases come from PubChem. Check identity and measured content against your lot's certificate.

What the research covers

Published work on kisspeptin falls into six areas. Each summary below states the model used.

Receptor pharmacology in cell culture

One study purified peptides from human placenta. They bound rat and human GPR54 with low nanomolar affinity. The receptors were expressed in Chinese hamster ovary cells. The peptides triggered phosphoinositide hydrolysis, calcium mobilization and MAP kinase phosphorylation. They also inhibited proliferation of the transfected cells (Kotani et al., 2001). A parallel report cloned the same receptor as AXOR12.

It found the highest receptor transcript levels in brain, pituitary and placenta (Muir et al., 2001). The C-terminal amide is needed for activity. Matrix metalloproteinases were used to cut the decapeptide between Gly and Leu. The cut peptide could no longer act on the receptor (Takino et al., 2003).

Human genetics of the KISS1R pathway

Two 2003 reports linked loss-of-function changes in GPR54 to absent pubertal development. One mapped a consanguineous family to chromosome 19p13. It found a homozygous 155-nucleotide deletion in GPR54 in all five affected siblings (de Roux et al., 2003). The other found an L148S change in one pedigree. It also found compound changes in an unrelated case. The variant receptor showed lower inositol phosphate accumulation in transfected cells. The same paper found the matching phenotype in Gpr54-deficient mice (Seminara et al., 2003).

Gonadotropin release in rodent models

In mice, kisspeptin-10 and kisspeptin-54 were given into the lateral cerebral ventricle. Both raised luteinizing hormone (LH). Giving a GnRH antagonist first blocked this effect. KISS1 transcripts were mapped to hypothalamic nuclei involved in gonadotropin control (Gottsch et al., 2004). In adult male rats, kisspeptin-10 was given both centrally and peripherally.

It raised LH, follicle-stimulating hormone (FSH) and total testosterone. The peptide also released LHRH from hypothalamic explants. Isolated pituitary fragments did not respond (Thompson et al., 2004; Navarro et al., 2005). Double-label in situ hybridization found that 77 percent of GnRH neurons co-express the receptor transcript (Irwig et al., 2004).

Primate and sheep models

In sheep, kisspeptin was given into the cerebral ventricle. Direct measurement showed that it released GnRH into cerebrospinal fluid. Serum LH rose at the same time. Kisspeptin had no effect in Gpr54-null mice. This places the action at the GnRH neuron (Messager et al., 2005). In agonadal juvenile monkeys, kisspeptin-10 triggered a GnRH discharge. A GnRH-receptor antagonist abolished it.

Hypothalamic KISS1 transcript levels also rose across the pubertal transition (Shahab et al., 2005). Continuous infusion in the same model gave a brisk response for about three hours. Then the response fell sharply. A later challenge with the peptide no longer worked, while GnRH itself still did. The authors read this as receptor desensitization (Seminara et al., 2006).

Human clinical studies

A few academic groups have run controlled studies in volunteers. In one, kisspeptin-54 was compared with saline in six healthy men. It raised LH, FSH and testosterone. The measured plasma half-life was near 28 minutes (Dhillo et al., 2005). Kisspeptin-10 raised LH in healthy men. Giving it continuously increased pulse frequency and secretory burst mass (George et al., 2011). A separate group reported that giving the peptide once advanced the next LH pulse. It then delayed the following pulse by roughly one interpulse interval.

The authors read this as resetting the hypothalamic pulse generator (Chan et al., 2011). Responses differ by sex and cycle phase. Women in the follicular phase showed no measurable gonadotropin response at the amounts tested. Men, and women in the preovulatory phase, did respond (Jayasena et al., 2011). A head-to-head comparison was run in healthy men. It found kisspeptin-10 and kisspeptin-54 broadly similar to each other. Both were weaker than GnRH (Jayasena et al., 2015).

Metastasis, placenta and peripheral tissues

Full-length KiSS-1 complementary DNA was transfected into melanoma cells. This suppressed metastasis in mice in an expression-dependent way. It did not block tumor formation (Lee et al., 1996). In primary human trophoblasts, kisspeptin-10 raised calcium inside the cells. It inhibited migration in explant and transwell assays. Proliferation did not change (Bilban et al., 2004). Receptor and peptide have also been found in human aorta, coronary artery and umbilical vein.

There, the peptides constricted isolated vessel rings (Mead et al., 2007). They have also been found in pancreatic islets. Reported effects on insulin secretion there have gone in both directions. The direction depended on the preparation (Hauge-Evans et al., 2006; Bowe et al., 2009). A broad review of the field covers these strands together (Pinilla et al., 2012).

Key studies

1. Lee JH, et al. "KiSS-1, a novel human malignant melanoma metastasis-suppressor gene." J Natl Cancer Inst. 1996. PMID 8944003. DOI 10.1093/jnci/88.23.1731. Melanoma cell lines and mouse metastasis assays: identification of the gene.
2. Ohtaki T, et al. "Metastasis suppressor gene KiSS-1 encodes peptide ligand of a G-protein-coupled receptor." Nature. 2001. PMID 11385580. DOI 10.1038/35079135. Peptide purification from human placenta plus transfected cell and mouse assays.
3. Kotani M, et al. "The metastasis suppressor gene KiSS-1 encodes kisspeptins, the natural ligands of the orphan G protein-coupled receptor GPR54." J Biol Chem. 2001. PMID 11457843. DOI 10.1074/jbc.M104847200. Cell culture: receptor binding and signaling by the 54, 14, 13 and 10 residue peptides.
4. Seminara SB, et al. "The GPR54 gene as a regulator of puberty." N Engl J Med. 2003. PMID 14573733. DOI 10.1056/NEJMoa035322. Human pedigree genetics, transfected cells and Gpr54-deficient mice.
5. Gottsch ML, et al. "A role for kisspeptins in the regulation of gonadotropin secretion in the mouse." Endocrinology. 2004. PMID 15217982. DOI 10.1210/en.2004-0431. Mouse model: central delivery, GnRH antagonist block, hypothalamic transcript mapping.
6. Messager S, et al. "Kisspeptin directly stimulates gonadotropin-releasing hormone release via G protein-coupled receptor 54." Proc Natl Acad Sci U S A. 2005. PMID 15665093. DOI 10.1073/pnas.0409330102. Mouse and sheep models: GnRH release measured in cerebrospinal fluid.
7. Shahab M, et al. "Increased hypothalamic GPR54 signaling: a potential mechanism for initiation of puberty in primates." Proc Natl Acad Sci U S A. 2005. PMID 15684075. DOI 10.1073/pnas.0409822102. Rhesus monkey model: GnRH discharge and transcript levels across puberty.
8. George JT, et al. "Kisspeptin-10 is a potent stimulator of LH and increases pulse frequency in men." J Clin Endocrinol Metab. 2011. PMID 21632807. DOI 10.1210/jc.2011-0089. Human clinical study in healthy men: deconvolution analysis of luteinizing hormone pulses.
9. Jayasena CN, et al. "Direct comparison of the effects of intravenous kisspeptin-10, kisspeptin-54 and GnRH on gonadotrophin secretion in healthy men." Hum Reprod. 2015. PMID 26089302. DOI 10.1093/humrep/dev143. Single-blind placebo-controlled human study comparing the two isoforms with GnRH.

Handling and storage of lyophilized kisspeptin

General lab practice for this material:

• Store the lyophilized powder at -20°C, protected from light, until use. Storage guidance is on the product page.
• Let the sealed vial reach room temperature before opening. This keeps moisture from condensing on the powder.
• Matrix metalloproteinases cleave kisspeptin-10 at the Gly-Leu bond. The cleaved peptide no longer activates the receptor (Takino et al., 2003). So make working solutions fresh when the medium or tissue preparation carries protease activity.
• In one human study, the measured plasma half-life of kisspeptin-54 was about 28 minutes (Dhillo et al., 2005). That is short next to typical incubation times. It is worth building into sampling schedules.
• After reconstitution, keep solutions at 2 to 8°C and protected from light. Split stock into single-use aliquots to avoid freeze/thaw cycles.
• Record the lot number and keep its certificate with your notes. For quantitative work, use the measured content and formula on the certificate, not the label mass.

Frequently asked questions

What is kisspeptin?

Kisspeptin is a family of peptides encoded by the KISS1 gene. They act on the receptor KISS1R, also known as GPR54. They were identified in 2001 as that receptor's natural ligands (Ohtaki et al., 2001; Kotani et al., 2001). They are studied in cell culture, rodent, primate and human models of the hypothalamic-pituitary-gonadal axis.

What is the difference between kisspeptin-10 and kisspeptin-54?

Kisspeptin-54, also called metastin, is the 54-residue peptide. Kisspeptin-10 is its C-terminal decapeptide, residues 45 to 54. Both carry the C-terminal RFamide motif. Both bind the receptor with similar affinity in vitro. In one head-to-head human study, the two isoforms produced broadly similar gonadotropin responses (Jayasena et al., 2015). A rodent analog study found the shorter peptide less durable in vivo. The authors put this down to faster breakdown or clearance (Curtis et al., 2010).

Is kisspeptin a peptide hormone?

Papers describe it as a neuropeptide that acts upstream of GnRH neurons, not on the pituitary directly. Two findings support this. Isolated pituitary fragments did not respond, while hypothalamic explants released LHRH (Thompson et al., 2004). And GnRH antagonists blocked the response in vivo (Gottsch et al., 2004).

Why do sources list different molecular weights for kisspeptin?

They usually describe different peptides or different salt forms. The free kisspeptin-10 peptide on the product page (C₆₃H₈₃N₁₇O₁₄) is 1302.4 g/mol. Kisspeptin-54 has 54 residues rather than 10, so it is heavier. Trifluoroacetate or acetate salt forms of either peptide add mass. For quantitative work, use the formula and measured content on your lot's certificate.

How should kisspeptin powder be stored?

Keep the lyophilized powder at -20°C and protected from light. After reconstitution, store the solution at 2 to 8°C, protected from light. Avoid freeze/thaw cycles. These are the conditions listed on the product page.

Where can researchers buy kisspeptin?

Disguised Alpha sells it for laboratory research. It is third-party tested, with the certificate published on the product page: Kisspeptin (10MG).

Related compounds and guides

• PT-141: a melanocortin peptide also studied in reproductive-pathway models.
• Oxytocin: a neurohypophyseal peptide. Giving kisspeptin raised oxytocin secretion in early rat work (Kotani et al., 2001).
• PT-141 research guide
• Oxytocin research guide
• GHK-Cu research guide
• COA portal: every published certificate, by lot.

This product is for research use only. It has not been evaluated for safety or effectiveness in humans. Not for human consumption. All products are intended for laboratory research purposes only.

Certificates of analysis

Each tested batch of Kisspeptin has its own certificate page with the full lab results.

• Batch KS02, tested Jul 15, 2026
• Batch KP02, tested Jun 10, 2026
• Batch #34492, tested Apr 23, 2026

Research basics

• What is a peptide?
• What is a certificate of analysis (COA)?
• What does lyophilized mean?
• What are peptide bioregulators?