Kisspeptin (Kisspeptin-10 / Metastin Fragment)
Also Known AsKisspeptin-10 · KP-10 · Metastin · KISS1
Kisspeptin was discovered in 1996 as a metastasis suppressor gene product (KISS1) at Penn State College of Medicine. Its role in reproductive neuroendocrinology was established in 2003 when loss-of-function mutations in the kisspeptin receptor (GPR54/KISS1R) were found to cause hypogonadotropic hypogonadism, revealing kisspeptin as the master upstream regulator of the HPG axis.
Tyr-Asn-Trp-Asn-Ser-Phe-Gly-Leu-Arg-Phe-NH₂ (KP-10)How Kisspeptin Works
GnRH Neuron Activation
Kisspeptin binds KISS1R (GPR54) on GnRH neurons in the hypothalamus, directly stimulating GnRH pulse generation and release. This is the primary physiological trigger for GnRH secretion and represents the 'master switch' of the hypothalamic-pituitary-gonadal (HPG) axis.
LH/FSH Release Cascade
By stimulating GnRH release, kisspeptin indirectly triggers pituitary gonadotropin secretion (LH and FSH). The LH pulse pattern determines testosterone/estrogen production, making kisspeptin the ultimate upstream regulator of reproductive hormone output.
Metabolic-Reproductive Integration
Kisspeptin neurons integrate metabolic signals (leptin, insulin, ghrelin) with reproductive function, serving as the molecular link between energy status and fertility. This explains why caloric restriction suppresses reproduction — it reduces kisspeptin signaling.
Published Research
Reproductive Endocrinology
StrongClinical studies demonstrate that kisspeptin administration potently stimulates LH, FSH, and testosterone/estrogen release in humans. Phase 2 trials for IVF applications show kisspeptin can safely trigger oocyte maturation with reduced OHSS (ovarian hyperstimulation syndrome) risk compared to hCG — a significant clinical advantage.
Male Hypogonadism & Testosterone
ModerateHuman studies demonstrate dose-dependent LH and testosterone elevations following kisspeptin administration in healthy men and men with functional hypothalamic hypogonadism. Unlike exogenous testosterone, kisspeptin stimulates endogenous production through the natural HPG axis, maintaining spermatogenesis.
Sexual Arousal & Brain Activation
ModeratefMRI studies by Waljit Dhillo's group at Imperial College London demonstrate that kisspeptin enhances brain processing of sexual and romantic stimuli, increasing activation in limbic and reward areas. This represents a novel, non-dopaminergic pathway for sexual function that is distinct from melanocortin (PT-141) or PDE5 mechanisms.
Fertility & IVF
StrongClinical trials for IVF trigger applications show that kisspeptin can safely induce final oocyte maturation while dramatically reducing the risk of ovarian hyperstimulation syndrome (OHSS), a potentially life-threatening complication of standard hCG triggers. This represents the most advanced clinical application of kisspeptin.
Safety Profile
Clinical trials with kisspeptin-54 and kisspeptin-10 in healthy volunteers and IVF patients report excellent tolerability. No serious adverse events. Effects are physiological (stimulating endogenous hormone pathways) rather than pharmacological, providing a wide safety margin. Self-limiting action due to tachyphylaxis with continuous dosing.
Handling & Storage
Reconstitute with bacteriostatic water. Kisspeptin-10 is the minimal active fragment with full receptor affinity. Store reconstituted solution at 2-8°C and use within 21 days. Lyophilized powder stable at -20°C. Sensitive to oxidation — avoid repeated freeze-thaw cycles.
Peer-Reviewed Literature
- 1
Kisspeptin-54 stimulates the hypothalamic-pituitary gonadal axis in human males
Dhillo WS, Chaudhri OB, Patterson M, et al.
- 2
Subcutaneous injection of kisspeptin-54 acutely stimulates gonadotropin secretion in women with hypothalamic amenorrhea
Jayasena CN, Nijher GMK, Chaudhri OB, et al.
- 3
Kisspeptin modulates sexual and emotional brain processing in humans
Comninos AN, Wall MB, Demetriou L, et al.
- 4
Efficacy of kisspeptin-54 to trigger oocyte maturation in women at high risk of ovarian hyperstimulation syndrome (OHSS) during in vitro fertilization (IVF) therapy
Abbara A, Jayasena CN, Christopoulos G, et al.
Kisspeptin FAQ
What is Kisspeptin?
Kisspeptin is a neuropeptide encoded by the KISS1 gene that acts as the master upstream regulator of the hypothalamic-pituitary-gonadal (HPG) axis. By activating KISS1R (GPR54) on GnRH neurons, it initiates the entire cascade of reproductive hormone production. Its discovery in 2003 fundamentally changed understanding of reproductive neuroendocrinology.
How does Kisspeptin affect testosterone?
Kisspeptin stimulates testosterone production through the natural HPG axis: kisspeptin → GnRH release → LH secretion → testicular testosterone synthesis. Unlike exogenous testosterone which suppresses the HPG axis, kisspeptin activates it, maintaining normal spermatogenesis and endogenous production capacity.
What is the difference between Kisspeptin and PT-141 for sexual function?
They work through entirely different pathways. PT-141 activates melanocortin-4 receptors (MC4R) in the hypothalamus for central arousal. Kisspeptin activates KISS1R on GnRH neurons to stimulate reproductive hormones AND enhances limbic brain processing of sexual stimuli. They are mechanistically complementary.
Is Kisspeptin being used in clinical IVF?
Yes. Kisspeptin is in advanced clinical trials as a safer alternative to hCG for triggering final oocyte maturation in IVF. It dramatically reduces the risk of ovarian hyperstimulation syndrome (OHSS) — a potentially life-threatening complication — while maintaining oocyte quality. Clinical research is led by groups at Imperial College London and Hammersmith Hospital.
Kisspeptin Products
All compounds 99%+ purity, verified by Janoshik Analytical. GMP-manufactured lyophilized powder.
Kisspeptin
5mgThe master switch of your sex hormones — triggers the full cascade from brain to testosterone/estrogen production, boosting libido, arousal, and fertility in both sexes.
- Triggers the hormonal cascade that drives sex drive and arousal
- Boosts testosterone in men and estrogen in women naturally
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Disclaimer: This monograph is provided for educational and research purposes only. G26x Peptides products are sold exclusively as research chemicals. They are not intended for human consumption, therapeutic use, or as dietary supplements. All research should be conducted in compliance with applicable laws and institutional review board protocols. Information presented here is sourced from published peer-reviewed literature and does not constitute medical advice.