Reduced anorexigenic efficacy of leptin, but not of the melanocortin receptor agonist melanotan-II, predicts diet-induced obesity in rats.

van Dijk G, de Vries K, Nyakas C, Buwalda B, Adage T, Kuipers F, Kas MJ, Adan RA, Wilkinson CW, Thiele TE, Scheurink AJ

Endocrinology15 Sept 2005Cited by 8 (Europe PMC)

PMID16166222PMCIDPMC1360237DOI10.1210/en.2005-0472PepBankPUB-16166222

Summary

The text of this summary is not shown here, because the article license does not allow reuse. Read it at the source (opens in a new tab)

Text rights: Publisher copyright. Results still quote short attributed sentences.

Results from this study5

5 results from studies that gave the peptide. No result from this study comes from people.

01AnimalAnimal study (in vivo)Efficacy outcome
In Wistar rats, third-cerebroventricular melanotan II at an anorexigenic dose increased plasma ACTH, to a degree comparable with leptin.
In plain wordsIn rats, melanotan II given into the brain raised the stress hormone ACTH, about as much as leptin did.
Peptide
Melanotan II
Outcome
IncreasePlasma ACTH
Study
ratn: not reported in source
outbred Wistar rats
Comparator
Leptin (equi-anorexigenic dose)
Outcome group
Stress hormones · Endocrine and hormones
Studied dose
Dose not stated · third-cerebroventricularAs given in this study (rat).
Source sentences
Summary
Third-cerebroventricular administration of equi-anorexigenic doses of leptin and of the MC agonist melanotan-II caused comparable increases in plasma ACTH and corticosterone levels and c-Fos-labeling in approximately 70% of paraventricular hypothalamic (PVN) neuronal cell bodies containing CRH.
1 context sentence(design, population, supporting numbers)
Summary · context
Although leptin or MC receptor insensitivity has been proposed to be associated with obesity, the present study compared central leptin and MC receptor stimulation on some of the above-mentioned parameters and investigated whether these treatments predict proneness to diet-induced obesity (DIO) in outbred Wistar rats.
Report a problemFND-1616622201
02AnimalAnimal study (in vivo)Efficacy outcome
In Wistar rats, third-cerebroventricular melanotan II at an anorexigenic dose increased plasma corticosterone, to a degree comparable with leptin.
In plain wordsIn rats, melanotan II given into the brain raised the stress hormone corticosterone, about as much as leptin did.
Peptide
Melanotan II
Outcome
IncreasePlasma corticosterone
Study
ratn: not reported in source
outbred Wistar rats
Comparator
Leptin (equi-anorexigenic dose)
Outcome group
Stress hormones · Endocrine and hormones
Studied dose
Dose not stated · third-cerebroventricularAs given in this study (rat).
Source sentences
Summary
Third-cerebroventricular administration of equi-anorexigenic doses of leptin and of the MC agonist melanotan-II caused comparable increases in plasma ACTH and corticosterone levels and c-Fos-labeling in approximately 70% of paraventricular hypothalamic (PVN) neuronal cell bodies containing CRH.
1 context sentence(design, population, supporting numbers)
Summary · context
Although leptin or MC receptor insensitivity has been proposed to be associated with obesity, the present study compared central leptin and MC receptor stimulation on some of the above-mentioned parameters and investigated whether these treatments predict proneness to diet-induced obesity (DIO) in outbred Wistar rats.
Report a problemFND-1616622202
03AnimalAnimal study (in vivo)Mechanism
In Wistar rats, melanotan II increased c-Fos labeling in about 70% of paraventricular hypothalamic CRH neurons, comparable with leptin.
In plain wordsIn rats, melanotan II activated about 70% of a group of stress-control brain cells, similar to leptin.
Peptide
Melanotan II
Outcome
Increasec-Fos labeling in PVN CRH neurons
Study
ratn: not reported in source
outbred Wistar rats
Comparator
Leptin (equi-anorexigenic dose)
Outcome group
Brain and neuronal activity · Nervous system and cognition
Studied dose
Dose not stated · third-cerebroventricularAs given in this study (rat).
Measurements
c-Fos-labeled PVN CRH neurons
≈ 70%
melanotan-II
Source sentences
Summary
Third-cerebroventricular administration of equi-anorexigenic doses of leptin and of the MC agonist melanotan-II caused comparable increases in plasma ACTH and corticosterone levels and c-Fos-labeling in approximately 70% of paraventricular hypothalamic (PVN) neuronal cell bodies containing CRH.
1 context sentence(design, population, supporting numbers)
Summary · context
Although leptin or MC receptor insensitivity has been proposed to be associated with obesity, the present study compared central leptin and MC receptor stimulation on some of the above-mentioned parameters and investigated whether these treatments predict proneness to diet-induced obesity (DIO) in outbred Wistar rats.
Report a problemFND-1616622203
04AnimalAnimal study (in vivo)Efficacy outcome
In rats on a diet-induced obesity prediction study, the anorexigenic efficacy of melanotan II was not correlated with any parameter linked to diet-induced obesity.
In plain wordsIn rats, how strongly melanotan II cut food intake did not predict later diet-induced obesity.
Peptide
Melanotan II
Outcome
No significant changeAnorexigenic efficacy of MTII versus diet-induced obesity parameters
Study
ratn: not reported in source
outbred Wistar rats
Outcome group
Appetite and food intake · Metabolic and weight
Studied dose
Dose not stated · third-cerebroventricularAs given in this study (rat).
Source sentences
Summary
In the DIO prediction study, anorexigenic efficacy of melanotan-II was not correlated with any parameter linked to DIO
1 context sentence(design, population, supporting numbers)
Summary · context
Although leptin or MC receptor insensitivity has been proposed to be associated with obesity, the present study compared central leptin and MC receptor stimulation on some of the above-mentioned parameters and investigated whether these treatments predict proneness to diet-induced obesity (DIO) in outbred Wistar rats.
Report a problemFND-1616622204
05AnimalAnimal study (in vivo)Mechanism
In rats, the anorexigenic efficacy of melanotan II was highly correlated with melanocortin in situ binding and with CRH immunoreactivity in the paraventricular nucleus.
In plain wordsIn rats, how strongly melanotan II cut food intake matched the amount of melanocortin receptor binding and CRH signal in one brain area.
Peptide
Melanotan II
Outcome
Not applicableAnorexigenic efficacy of MTII versus MC in situ binding and PVN CRH immunoreactivity
Study
ratn: not reported in source
outbred Wistar rats
Outcome group
Receptor activity and mechanism · Nervous system and cognition
Studied dose
Dose not stated · third-cerebroventricularAs given in this study (rat).
Source sentences
Summary
In the DIO prediction study, anorexigenic efficacy of melanotan-II was not correlated with any parameter linked to DIO but was highly correlated with MC in situ binding (with labeled [Nle(4),D-Phe(7)]alpha-MSH) as well as CRH immunoreactivity in the PVN of DIO rats.
1 context sentence(design, population, supporting numbers)
Summary · context
Although leptin or MC receptor insensitivity has been proposed to be associated with obesity, the present study compared central leptin and MC receptor stimulation on some of the above-mentioned parameters and investigated whether these treatments predict proneness to diet-induced obesity (DIO) in outbred Wistar rats.
Report a problemFND-1616622205

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Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

Version 2Current
10 Oct 2026, 09:43 UTC
Study results updated
Version 1
9 Oct 2026, 03:04 UTC
First added · source update from Europe PMC

Subjects

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