PLGamide characterization and role in osmoregulation in leech brain.

Salzet M, Deloffre L

Brain research. Molecular brain research1 Mar 2000

PMID10719226DOI10.1016/s0169-328x(99)00345-9PepBankPUB-10719226

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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 study7

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

01LabEx vivo tissueMechanism
In leech brain experiments, PLGamide did not bind mu-alkaloid opioid receptors.
In plain wordsIn lab tests with leech brain, PLGamide did not bind mu-opioid receptors.
Peptide
MIF-1 (Pro-Leu-Gly-NH2)
Outcome
No significant changeMu-opioid receptor binding
Study
leechn: not reported in source
leech brain
Outcome group
Receptor activity and mechanism · Nervous system and cognition
Studied dose
Dose not stated
Source sentences
Summary
PLGamide did not bind to mu-alkaloid opioid receptors and did not stimulate NO release.
1 context sentence(design, population, supporting numbers)
Summary · context
Finally, since in vertebrates MIF-1 belongs to the non-classical opioid peptide family, we studied its binding displacement, in contrast to morphine, on mu-receptors and on nitric oxide (NO) release experiments in leech brain.
Report a problemFND-1071922606
02LabEx vivo tissueMechanism
In leech brain experiments, PLGamide did not stimulate nitric oxide release.
In plain wordsIn lab tests with leech brain, PLGamide did not stimulate nitric oxide release.
Peptide
MIF-1 (Pro-Leu-Gly-NH2)
Outcome
No significant changeNitric oxide release
Study
leechn: not reported in source
leech brain
Outcome group
Receptor activity and mechanism · Nervous system and cognition
Studied dose
Dose not stated
Source sentences
Summary
PLGamide did not bind to mu-alkaloid opioid receptors and did not stimulate NO release.
1 context sentence(design, population, supporting numbers)
Summary · context
Finally, since in vertebrates MIF-1 belongs to the non-classical opioid peptide family, we studied its binding displacement, in contrast to morphine, on mu-receptors and on nitric oxide (NO) release experiments in leech brain.
Report a problemFND-1071922607

Natural levels measured4

These results measure the body's own peptide. Nobody was given the peptide. They are not evidence about taking it. They are left out of key results, evidence counts and charts.

03LabEndogenous levelEx vivo tissueMechanism
In Theromyzon tessulatum brain, neurons showed immunoreactivity to an antiserum directed against PLGamide.
In plain wordsIn leeches, researchers detected neurons reactive to an antibody against the body's own PLGamide.
Peptide
MIF-1 (Pro-Leu-Gly-NH2)
Outcome
Not applicablePLGamide-immunoreactive neurons
Study
Theromyzon tessulatumn: not reported in source
leech brain
Outcome group
Receptor activity and mechanism · Nervous system and cognition
Source sentences
Summary
Neurons immunoreactive to an antiserum specifically directed against the Prolyl-Leucyl-Glycinamide peptide (PLGamide: Melanocyte Inhibiting Factor: MIF) were detected in the brain of the leech Theromyzon tessulatum.
This result measures the body's own MIF-1 (Pro-Leu-Gly-NH2). Nobody was given the peptide. It is not evidence about taking it.
Report a problemFND-1071922601
04LabEndogenous levelEx vivo tissueMechanism
In Theromyzon tessulatum, brain PLGamide-like material peaked at stage 3B, associated with maximal water uptake and coelomic vitellogenin accumulation.
In plain wordsIn leeches, natural PLGamide-like levels peaked at stage 3B, linked to maximal water uptake and yolk-protein accumulation.
Peptide
MIF-1 (Pro-Leu-Gly-NH2)
Outcome
IncreaseLife-cycle PLGamide-like material levels
Study
Theromyzon tessulatumn: not reported in source
leech brain
Comparator
other physiological life-cycle stages
Outcome group
Receptor activity and mechanism · Nervous system and cognition
Source sentences
Summary
Radioimmunoassay titrations of the PLGamide-like material at different physiological stages of the life cycle indicated a maximal amount at stage 3B, which is correlated to phase of both maximal water uptake and coelomic vitellogenin accumulation.
This result measures the body's own MIF-1 (Pro-Leu-Gly-NH2). Nobody was given the peptide. It is not evidence about taking it.
Report a problemFND-1071922602
05LabEndogenous levelEx vivo tissueMechanism
In Hirudo medicinalis and Erpobdella octoculata brains, PLGamide-reactive material amounts did not differ with sexual maturation.
In plain wordsIn these leeches, natural PLGamide-like levels did not differ with sexual maturation.
Peptide
MIF-1 (Pro-Leu-Gly-NH2)
Outcome
No significant changePLGamide-like material and sexual maturation
Study
Hirudo medicinalis and Erpobdella octoculatan: not reported in source
leech brain
Comparator
different degrees of sexual maturation
Outcome group
Receptor activity and mechanism · Nervous system and cognition
Source sentences
Summary
In brains of the Gnatobdellid leech Hirudo medicinalis and the Pharyngobdellid leech Erpobdella octoculata, anti-PLGamide material was also detected with an amount not differing with the degree of sex maturation of the animals, confirming the link between osmoregulation and ovogenesis in rhynchobdellid leeches.
This result measures the body's own MIF-1 (Pro-Leu-Gly-NH2). Nobody was given the peptide. It is not evidence about taking it.
Report a problemFND-1071922604
06LabEndogenous levelEx vivo tissueMechanism
In leech brain extracts, biochemical separation and Edman degradation identified authentic MIF‑1.
In plain wordsIn lab tests, researchers identified the body's own MIF‑1 in leech brain extracts.
Peptide
MIF-1 (Pro-Leu-Gly-NH2)
Outcome
Not applicableAuthentic MIF-1 identification
Study
leechn: not reported in source
leech brain extracts
Outcome group
Receptor activity and mechanism · Nervous system and cognition
Source sentences
Summary
Using a combination of biochemical techniques including high-pressure gel permeation chromatography followed by reversed-phase HPLC on brain extracts and Edman degradation, we demonstrated the presence of an authentic MIF-1 peptide in leech brain.
This result measures the body's own MIF-1 (Pro-Leu-Gly-NH2). Nobody was given the peptide. It is not evidence about taking it.
Report a problemFND-1071922605

Studies that did not test the peptide alone1

In this study, MIF-1 (Pro-Leu-Gly-NH2) was a lab tool or a carrier, part of a mix, or the subject of a lab method. These results are not evidence about taking MIF-1 (Pro-Leu-Gly-NH2).

07AnimalNot a test of MIF-1 (Pro-Leu-Gly-NH2) aloneAnimal study (in vivo)Mechanism
In leech experiments, cerebral PLGamide-like material showed antidiuretic activity that would permit water retention and coelomic yolk-protein accumulation at stage 3B.
In plain wordsIn leeches, brain PLGamide-like material showed antidiuretic activity that could permit water retention and yolk-protein accumulation.
Peptide
MIF-1 (Pro-Leu-Gly-NH2)
Outcome
IncreaseAntidiuretic activity
Study
Theromyzon tessulatumn: not reported in source
leech osmoregulation
Outcome group
Receptor activity and mechanism · Kidney and urinary
Source sentences
Summary
In vivo experiments demonstrate that this cerebral PLGamide-like material is an anti-diuretic factor that would act at stage 3B in order to permit a water uptake leading to water retention allowing coelomic yolk protein accumulation.
In this study, MIF-1 (Pro-Leu-Gly-NH2) was a lab tool or a carrier, part of a mix, or the subject of a lab method. This result is not evidence about taking MIF-1 (Pro-Leu-Gly-NH2).
Report a problemFND-1071922603

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

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
22 Oct 2026, 02:26 UTC
Study results updated
Version 1
21 Oct 2026, 18:59 UTC
First added · source update from Europe PMC

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