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Study · Animal study (in vivo) · mouse · 1979

2 results

Prolyl-leucyl-glycinamide, cyclo(leucylglycine), and derivatives block development of physical dependence on morphine in mice.

Walter R, Ritzmann RF, Bhargava HN, Flexner LB

Proceedings of the National Academy of Sciences of the United States of America1 Jan 1979Cited by 26 (Europe PMC)

PMID284370 (opens in a new tab)PMCIDPMC382973 (opens in a new tab)DOI10.1073/pnas.76.1.518 (opens in a new tab)PepBankPUB-00284370
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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 study2

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

  1. 01AnimalAnimal study (in vivo)Efficacy outcome

    In mice receiving chronic morphine, MIF prevented physical dependence measured by temperature changes during naloxone-induced withdrawal.

    In plain wordsIn mice receiving chronic morphine, MIF prevented physical dependence measured by temperature changes during withdrawal.

    Peptide
    MIF-1 (Pro-Leu-Gly-NH2)
    Outcome
    DecreasePhysical morphine dependence measured by withdrawal temperature changes
    Study

    mousen: not reported in source

    chronic morphine exposure
    Outcome group
    Receptor activity and mechanism · Nervous system and cognition
    Studied dose
    50 microgram daily · injectionAs given in this study (mouse).

    Source sentences

    Summary
    Pro-Leu-Gly-NH2 (MIF) and several structural analogues, all injected in 50-microgram doses daily in mice receiving morphine chronically, were found to prevent development of physical dependence as measured by changes in body temperature associated with naloxone-induced withdrawal.
    1 context sentence
    Summary · context
    Pro-Leu-Gly-NH2 (MIF) and several structural analogues, all injected in 50-microgram doses daily in mice receiving morphine chronically,
  2. 02AnimalAnimal study (in vivo)Efficacy outcome

    In mice, MIF blocked physical dependence on morphine at doses as low as 0.5 microgram per mouse.

    In plain wordsIn mice, MIF blocked physical dependence on morphine at doses as low as 0.5 microgram per mouse.

    Peptide
    MIF-1 (Pro-Leu-Gly-NH2)
    Outcome
    DecreasePhysical morphine dependence dose response
    Study

    mousen: not reported in source

    chronic morphine exposure
    Outcome group
    Receptor activity and mechanism · Nervous system and cognition
    Studied dose
    0.5 microgram per mouse · injectionAs given in this study (mouse).

    Source sentences

    Summary
    Dose-response studies, using again a protocol of daily injections of peptide at 50, 5, 0.5, 0.05, 0.005 microgram per mouse revealed MIF and cyclo(Leu-Gly) to be the most potent peptides and to be effective in blocking physical dependence to morphine at a dose as low as 0.5 and 0.05 microgram per mouse, respectively.
    1 context sentence
    Summary · context
    Pro-Leu-Gly-NH2 (MIF) and several structural analogues, all injected in 50-microgram doses daily in mice receiving morphine chronically,

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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.

  1. Version 2Current

    22 Oct 2026, 02:26 UTC

    Study results updated

  2. Version 1

    21 Oct 2026, 18:59 UTC

    First added · source update from Europe PMC

Subjects

Terms as the source lists them.

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