Melanin-concentrating hormone
The lateral-hypothalamus peptide that pushes appetite and rapid-eye-movement sleep, studied in animal brains and measured in human blood and brain
Melanin-concentrating hormone is a small cyclic peptide made by neurons deep in the hypothalamus. In fish it pales the skin, the job it was named for; in mammals it instead drives eating and body weight and promotes dreaming sleep. Infused into rodent brains it causes lasting overeating and obesity, and removing it makes animals lean. In people it is measured, in blood and in brain tissue, rather than given, and the drug development built on it has gone to molecules that block its receptor.
No established human dose Details ↓
Recommended Dosing
No established human dose
Melanin-concentrating hormone is studied in people by measurement, not by giving it: the human studies here assay it in plasma, brain tissue and cerebrospinal fluid. The doses that produce its effects, sustained overeating, obesity and more rapid-eye-movement sleep, come from infusing it into the brains of rodents, not from any human treatment.
What is it?
Melanin-concentrating hormone was first isolated from salmon, where it lightens the skin by gathering pigment, the opposite of what alpha-MSH does. The mammalian peptide has the same 19-residue cyclic structure, closed by a disulfide bond, but a different job: it is one of the brain's strongest signals to eat. It is made by a defined population of neurons in the lateral hypothalamus and the neighbouring zona incerta, which send fibres through much of the brain.
The weight story comes mostly from rodents, where the tools exist. Chronic infusion of the peptide into the brain ventricles of mice caused a slight weight gain on a normal diet and a clear gain, with sustained overeating and more fat, on a high-fat diet, along with higher glucose, insulin and leptin. Animals engineered to lack the peptide or its main receptor stay lean. In one striking experiment, deleting the peptide in leptin-deficient obese mice cut their body fat sharply, not by eating less but by burning more energy, which places it at a hub of energy balance downstream of leptin. The peptide also pushes animals toward sugar and calorie-dense drinks rather than sweet taste alone.
Its second clear role is in sleep. Its neurons fire fastest during rapid-eye-movement sleep, and activating them in mice increases that sleep stage. In a mouse model of narcolepsy, where the opposing orexin neurons are lost, activating these neurons triggered the abnormal sleep intrusions and cataplexy of the disease, and a receptor blocker almost abolished them. Reviews describe the system as a candidate target for sleep disorders, while cautioning that the loss-of-function evidence is less consistent than the gain-of-function evidence.
In people the peptide is studied by measurement, not infusion. A radioimmunoassay for human plasma set a fasting reference range of about 20 to 55 pg/mL across 231 people, with levels rising after a meal in older individuals and tracking body fat; the authors noted that the circulating peptide may not simply mirror its brain role. In brain tissue sampled during neurosurgery, levels in the amygdala were lowest during social interaction and rose after eating and at sleep onset, mirroring the opposite pattern of orexin. Its level is raised in the cerebrospinal fluid of patients with Alzheimer's disease and tracks the severity of cognitive impairment, and serum levels fall during antidepressant treatment in some patients.
Two things are often confused with the peptide and are not covered here. Beta-MSH is a different POMC-derived melanocortin, not a melanin-concentrating hormone, despite the shared history with pigment. And the MCHR1 antagonists developed as anti-obesity drugs are separate molecules; despite years of effort, none has reached approval.
Mechanism of Action
Melanin-concentrating hormone is made by lateral-hypothalamus neurons that project through the brain and acts on the MCHR1 receptor, and on MCHR2 in humans, to increase eating and promote rapid-eye-movement sleep.
Appetite
Infused into rodent brains it drives overeating and obesity; animals lacking it or its receptor stay lean.
REM sleep
Its neurons fire most during rapid-eye-movement sleep, and activating them increases it.
Mood and disease markers
Its levels shift in Alzheimer's cerebrospinal fluid and during antidepressant treatment.
Published Research
These are studies of melanin-concentrating hormone itself, read from their PubMed abstracts: measurements in human blood, brain and cerebrospinal fluid, the rodent brain-infusion and gene-deletion studies that define its role in weight and sleep, and four reviews. Studies whose point is a receptor-blocking drug are not carded here.
A reference range for the peptide in human blood
A radioimmunoassay validated by HPLC and mass spectrometry measured melanin-concentrating hormone in plasma from 231 people, setting a fasting range of about 20 to 55 pg/mL. Levels correlated with body-mass index in people with excess fat and rose after feeding in older individuals.
In the human brain, tied to eating and sleep
Measured in the human amygdala, melanin-concentrating hormone was lowest during social interaction and rose after eating. It also rose at sleep onset, the opposite of hypocretin, which rose at wake onset, linking the peptide to specific emotional states and to sleep induction.
Raised in Alzheimer's cerebrospinal fluid
In 33 patients with Alzheimer's disease and 33 healthy people, cerebrospinal fluid melanin-concentrating hormone was significantly higher in the patients (about 94 vs 85 pg/mL), correlated with tau proteins, and was higher in those with worse cognitive scores.
Serum levels fall with antidepressant treatment
In 30 patients with major depression, serum melanin-concentrating hormone did not differ from 30 controls at baseline but fell significantly over four weeks of treatment, an effect limited to those given mirtazapine and to women; levels correlated with measures of sleep.
Made in human skin
Melanin-concentrating hormone and its MCHR1 receptor were found as transcripts in human skin, with the peptide expressed by endothelial cells and the receptor by melanocytes and melanoma cells. In cultured melanocytes the peptide opposed alpha-MSH, reducing its effect on pigment-related signalling.
Present in human and rat brain, not blood
Immunoreactive melanin-concentrating hormone was highest in rat hypothalamus and its messenger RNA was found in rat and human hypothalamus but not peripheral tissues. It was not detected in human adrenal glands or in plasma from healthy people with the assay used.
Mapped in the human hypothalamus
An antiserum to salmon melanin-concentrating hormone revealed an extensive neuron system in the posterior lateral human hypothalamus, matching the pattern earlier described in the rat and co-expressing markers of alpha-MSH and a growth-hormone-releasing factor fragment.
Brain infusion causes obesity in mice
Fourteen days of melanin-concentrating hormone infused into the brain ventricles of mice caused a small weight gain on a normal diet and a clearer gain, with sustained overeating and more fat and liver weight, on a high-fat diet, along with higher glucose, insulin and leptin.
Loss of it makes leptin-deficient mice lean
Mice lacking both leptin and melanin-concentrating hormone had far less body fat than leptin-deficient mice despite unchanged overeating; the leanness came from higher energy expenditure, placing the peptide at a hub of energy balance downstream of leptin.
It drives intake of calorie-rich drinks
Injected into the brain ventricles of rats, melanin-concentrating hormone increased food and water intake and specifically raised intake of sucrose and glucose solutions but not of a non-caloric sweetener, indicating it drives intake tied to calories rather than sweet taste.
Its neurons drive narcoleptic REM intrusions
In orexin-null mice, a model of narcolepsy, chemically activating melanin-concentrating hormone neurons increased rapid-eye-movement sleep and triggered cataplexy and abnormal sleep transitions, while a receptor blocker nearly eliminated them, affirming the peptide promotes this sleep stage.
Its many roles in energy balance
A review of melanin-concentrating hormone across sleep, feeding and metabolism, describing its action through MCHR1 and MCHR2 and the interest in receptor agonists and antagonists for energy-balance disorders and obesity.
A cautious reading of its sleep role
A review of sleep-wake control by melanin-concentrating hormone neurons found gain-of-function studies consistently increase rapid-eye-movement sleep while loss-of-function studies do not reliably reduce it, proposing a role in shaping sleep responses to the environment rather than in spontaneous sleep.
REM sleep and depression
This review summarised evidence that melanin-concentrating hormone neurons fire most during rapid-eye-movement sleep and that microinjecting the peptide into raphe nuclei promotes that sleep and depression-like behaviour in animals, which antidepressants and a receptor blocker prevent.
A target for sleep disorders
A review of the system as a potential drug target for sleep disorders, noting its established role in rapid-eye-movement sleep and the long, largely unsuccessful history of developing MCHR1 antagonists for obesity.
No Established Human Dose
Melanin-concentrating hormone is studied in people by measurement, not by giving it: the human studies here assay it in plasma, brain tissue and cerebrospinal fluid. The doses that produce its effects, sustained overeating, obesity and more rapid-eye-movement sleep, come from infusing it into the brains of rodents, not from any human treatment. There is no human preparation and no established human dose.
What this rests on: PMID 28053003, PMID 23462990, PMID 12453827.
Educational information, not medical advice. The doses on this page come from approved labels, published studies and, where no study exists, amounts reported by users. None is a recommendation for you. An unapproved compound has no established safe or effective human dose, and products sold for “research use only” are not made or tested for people. Talk to a doctor before acting on anything on this site, including before you start, stop or change any medicine or dose. Full medical disclaimer.
What a Buyer Needs to Know
What is sold, how it is mixed, stored and taken, and what is known about its safety, quality and legal status. Each part names its source. Where we have none, it says unknown.
What is sold
Unknown: we hold no label and no published test that says what forms or vial sizes Melanin-concentrating hormone is sold in. A vial's own label is a seller's claim, not a source.
Mixing a vial: a worked example
Unknown: no human dose of Melanin-concentrating hormone has been established (see No Established Human Dose below), so there is no amount to work out. The reconstitution calculator does the arithmetic for any vial, water and dose.
Storage before and after mixing
Unknown: no label or published stability study on file says how to store Melanin-concentrating hormone, before or after mixing. The mixing guide sets out the general rules, with their sources: keep a mixed vial in the fridge, and use it promptly, as the bacteriostatic water label says of any drug dissolved in it. The 28 days often quoted is the limit for an opened multiple-dose vial from a manufacturer, an outer limit set for sterility, not a time a mixed solution has been shown to keep. Nobody has published how long Melanin-concentrating hormone stays intact once mixed.
How it is taken
Unknown: with no established human dose, there is no established way of taking Melanin-concentrating hormone. What the human studies gave and how is set out under No Established Human Dose.
What to expect, and when
Unknown: no cited half-life and no label or trial duration on this page says how long Melanin-concentrating hormone lasts or how long it was given. Results reported in the studies are under Published Research.
Side effects, and when to stop or get help
From the Side Effects section: In rodents, brain infusion caused overeating, weight gain and higher glucose and insulin (PMID 12453827); In a mouse model of narcolepsy, activating its neurons triggered cataplexy and abnormal sleep intrusions (PMID 30149182); No human safety data: it has not been administered to people in the sources read. Full list and cautions ↓
When to stop or get help: unknown; no label or trial on file sets rules for stopping Melanin-concentrating hormone. Treat a severe or unexpected reaction as a reason to stop and see a doctor.
Source: the Side Effects section below (“Melanin-concentrating hormone is measured in people, not given, so there are no human adverse-event data”).
Interactions
Unknown: a PubMed search for human interaction studies of Melanin-concentrating hormone (reviewed 2026-10-30) found none. Unknown is not the same as safe to combine.
Every peptide's record, with its source: the interaction matrix.
Checking what you bought
Unknown: no published independent test of Melanin-concentrating hormone products is in our lab-results database yet, so how products sold under this name measure up is not known.
To read a certificate of analysis, paste it into the COA decoder; it checks the measured mass against Melanin-concentrating hormone's expected mass, 2,386.9 Da, from this entry's molecular data. Trust & Verification explains what independent testing can and cannot show.
Legal status
US: Research Chemical (Not a medicine anywhere in the sources read). Sport: Prohibited (S0 catch-all).
Country by country ↓ · Regulatory tracker
Source: this entry's approval status and the WADA Prohibited List, as in Legal Status below.
Side Effects & Contraindications
Reported Side Effects
Melanin-concentrating hormone is measured in people, not given, so there are no human adverse-event data. These notes come from the animal studies above.
Contraindications & Cautions
No product label exists; the peptide is not given to people.
Legal Status
Melanin-concentrating hormone is a research peptide; it is not approved as a medicine anywhere in the sources read.
Frequently Asked Questions
?What is melanin-concentrating hormone?
A 19-amino-acid cyclic peptide made in the lateral hypothalamus. In mammals it drives eating and promotes dreaming sleep; in fish it pales the skin, which is how it was named.
?Does it make you gain weight?
In rodents, infusing it into the brain causes lasting overeating and obesity, and animals lacking it stay lean. In people it is measured, not given.
?What does it do in sleep?
Its neurons fire most during rapid-eye-movement sleep, and activating them in animals increases that sleep stage.
?Is it the same as beta-MSH?
No. Beta-MSH is a different melanocortin from the POMC protein; melanin-concentrating hormone comes from the PMCH gene and does the opposite to pigment cells.
?Can you take melanin-concentrating hormone?
There is no human preparation and no established human dose. It has been given only to animals, into the brain, in research.
?Why do drug companies target its receptor?
Because blocking MCHR1 was expected to reduce appetite. Many antagonists were developed for obesity, but none has reached approval.
References
- [clinical-trial] Naufahu J, et al. "Melanin-concentrating hormone in peripheral circulation in the human." J Endocrinol, 2017;232(3):513-523. PMID: 28053003.
- [clinical-trial] Blouin AM, et al. "Human hypocretin and melanin-concentrating hormone levels are linked to emotion and social interaction." Nat Commun, 2013;4:1547. PMID: 23462990.
- [clinical-trial] Schmidt FM, et al. "Cerebrospinal fluid melanin-concentrating hormone (MCH) and hypocretin-1 (HCRT-1, orexin-A) in Alzheimer's disease." PLoS One, 2013;8(5):e63136. PMID: 23667582.
- [clinical-trial] Schmidt FM, et al. "Dynamics of melanin-concentrating hormone (MCH) serum levels in major depressive disorder during antidepressant treatment." J Affect Disord, 2015;180:207-13. PMID: 25932975.
- [pubmed] Hoogduijn MJ, et al. "Melanin-concentrating hormone and its receptor are expressed and functional in human skin." Biochem Biophys Res Commun, 2002;296(3):698-701. PMID: 12176038.
- [pubmed] Takahashi K, et al. "Melanin-concentrating hormone in human and rat." Neuroendocrinology, 1995;61(5):493-8. PMID: 7617126.
- [pubmed] Bresson JL, et al. "Human hypothalamic neuronal system revealed with a salmon melanin-concentrating hormone (MCH) antiserum." Neurosci Lett, 1989;102(1):39-43. PMID: 2779843.
- [pubmed] Gomori A, et al. "Chronic intracerebroventricular infusion of MCH causes obesity in mice. Melanin-concentrating hormone." Am J Physiol Endocrinol Metab, 2003;284(3):E583-8. PMID: 12453827.
- [pubmed] Segal-Lieberman G, et al. "Melanin-concentrating hormone is a critical mediator of the leptin-deficient phenotype." Proc Natl Acad Sci U S A, 2003;100(17):10085-90. PMID: 12897241.
- [pubmed] Sakamaki R, et al. "Melanin-concentrating hormone enhances sucrose intake." Int J Mol Med, 2005;15(6):1033-9. PMID: 15870910.
- [pubmed] Naganuma F, et al. "Melanin-concentrating hormone neurons contribute to dysregulation of rapid eye movement sleep in narcolepsy." Neurobiol Dis, 2018;120:12-20. PMID: 30149182.
- [review] Al-Massadi O, et al. "Multifaceted actions of melanin-concentrating hormone on mammalian energy homeostasis." Nat Rev Endocrinol, 2021;17(12):745-755. PMID: 34608277.
- [review] Bandaru SS, et al. "Sleep-Wake Control by Melanin-Concentrating Hormone (MCH) Neurons: a Review of Recent Findings." Curr Neurol Neurosci Rep, 2020;20(12):55. PMID: 33006677.
- [review] Torterolo P, et al. "Melanin-Concentrating Hormone (MCH): Role in REM Sleep and Depression." Front Neurosci, 2015;9:475. PMID: 26733789.
- [review] Potter LE, et al. "The melanin-concentrating hormone system as a target for the treatment of sleep disorders." Front Neurosci, 2022;16:952275. PMID: 36177357.
- [other] UniProt P20382 (MCH_HUMAN), pro-MCH; peptide 147-165 is melanin-concentrating hormone (DFDMLRCMLGRVYRPCWQV), a 19-residue cyclic peptide with a Cys7-Cys16 disulfide bond. Read October 30, 2026. https://www.uniprot.org/uniprotkb/P20382/entry
Sources & Citations
Every study on this page was read from its PubMed record on October 30, 2026. Regulatory status comes from Drugs@FDA (openFDA) and the EMA medicines list, read the same day. Grey Peptides sells nothing and links to no vendor.
Medical Disclaimer: This content is for educational and informational purposes only. It is not medical advice, and nothing here is an instruction to obtain or use any compound. Talk to a licensed clinician about your own situation.