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Study · Animal study (in vivo) · rat · 1981

6 results

Inhibition of tolerance to the pharmacological effects of human beta-endorphin by prolyl-leucyl-glycinamide and cyclo(leucylglycine) in the rat.

Bhargava HN

The Journal of pharmacology and experimental therapeutics1 Aug 1981Cited by 27 (Europe PMC)

PMID6114170 (opens in a new tab)DOI10.1016/s0022-3565(25)32684-4 (opens in a new tab)PepBankPUB-06114170
Publisher pagePubMedAsk about this study
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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 study6

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

  1. 01AnimalAnimal study (in vivo)Efficacy outcome

    In rats, daily MIF blocked the development of tolerance to beta-endorphin analgesia.

    In plain wordsIn rats, daily MIF prevented tolerance to beta-endorphin pain relief.

    Peptide
    MIF-1 (Pro-Leu-Gly-NH2)
    Outcome
    DecreaseTolerance to beta-endorphin analgesia
    Study

    ratn: not reported in source

    Male Sprague-Dawley rats
    Outcome group
    Drug tolerance · Nervous system and cognition
    Studied dose
    2 mg/kg · subcutaneousAs given in this study (rat).

    Source sentences

    Summary
    Daily s.c. administration of Pro-Leu-Gly-NH2 (MIF) or cyclo(Leu-Gly) (2 mg/kg each) blocked the development of tolerance to the analgesic and cataleptic effects of beta-endorphin.
    1 context sentence
    Summary · context
    Acute intraventricular administration of human beta-endorphin (15 microgram) produced analgesia, hypothermia and catalepsy in male Sprague-Dawley rats.
  2. 02AnimalAnimal study (in vivo)Efficacy outcome

    In rats, daily MIF blocked the development of tolerance to beta-endorphin-induced catalepsy.

    In plain wordsIn rats, daily MIF prevented tolerance to beta-endorphin-induced catalepsy.

    Peptide
    MIF-1 (Pro-Leu-Gly-NH2)
    Outcome
    DecreaseTolerance to beta-endorphin catalepsy
    Study

    ratn: not reported in source

    Male Sprague-Dawley rats
    Outcome group
    Drug tolerance · Nervous system and cognition
    Studied dose
    2 mg/kg · subcutaneousAs given in this study (rat).

    Source sentences

    Summary
    Daily s.c. administration of Pro-Leu-Gly-NH2 (MIF) or cyclo(Leu-Gly) (2 mg/kg each) blocked the development of tolerance to the analgesic and cataleptic effects of beta-endorphin.
    1 context sentence
    Summary · context
    Acute intraventricular administration of human beta-endorphin (15 microgram) produced analgesia, hypothermia and catalepsy in male Sprague-Dawley rats.
  3. 03AnimalAnimal study (in vivo)Efficacy outcome

    In beta-endorphin-tolerant rats, MIF partially blocked beta-endorphin-induced hyperthermia.

    In plain wordsIn rats tolerant to beta-endorphin, MIF partly reduced the beta-endorphin-induced rise in body temperature.

    Peptide
    MIF-1 (Pro-Leu-Gly-NH2)
    Outcome
    DecreaseHyperthermia in beta-endorphin-tolerant rats
    Study

    ratn: not reported in source

    Male Sprague-Dawley rats
    Outcome group
    Body temperature · Whole body
    Studied dose
    Dose not stated

    Source sentences

    Summary
    The hyperthermic effect of beta-endorphin in beta-endorphin-tolerant rats was partially blocked by both MIF and cyclo(Leu-Gly).
    1 context sentence
    Summary · context
    Acute intraventricular administration of human beta-endorphin (15 microgram) produced analgesia, hypothermia and catalepsy in male Sprague-Dawley rats.
  4. 04AnimalAnimal study (in vivo)Efficacy outcome

    In rats given repeated saline injections, multiple MIF injections did not alter beta-endorphin analgesia.

    In plain wordsIn rats given repeated saline injections, multiple MIF injections did not change beta-endorphin pain relief.

    Peptide
    MIF-1 (Pro-Leu-Gly-NH2)
    Outcome
    No significant changeBeta-endorphin analgesia without prior beta-endorphin exposure
    Study

    ratn: not reported in source

    Male Sprague-Dawley rats
    Outcome group
    Pain · Nervous system and cognition
    Studied dose
    Dose not stated

    Source sentences

    Summary
    Multiple injections of MIF or cyclo(Leu-Gly) did not alter beta-endorphin-induced analgesia, catalepsy and hypothermia in rats which were given repeated intraventricular injections of saline.
    1 context sentence
    Summary · context
    Acute intraventricular administration of human beta-endorphin (15 microgram) produced analgesia, hypothermia and catalepsy in male Sprague-Dawley rats.
  5. 05AnimalAnimal study (in vivo)Efficacy outcome

    In rats given repeated saline injections, multiple MIF injections did not alter beta-endorphin-induced catalepsy.

    In plain wordsIn rats given repeated saline injections, multiple MIF injections did not change beta-endorphin-induced catalepsy.

    Peptide
    MIF-1 (Pro-Leu-Gly-NH2)
    Outcome
    No significant changeBeta-endorphin catalepsy without prior beta-endorphin exposure
    Study

    ratn: not reported in source

    Male Sprague-Dawley rats
    Outcome group
    Exercise and physical function · Nervous system and cognition
    Studied dose
    Dose not stated

    Source sentences

    Summary
    Multiple injections of MIF or cyclo(Leu-Gly) did not alter beta-endorphin-induced analgesia, catalepsy and hypothermia in rats which were given repeated intraventricular injections of saline.
    1 context sentence
    Summary · context
    Acute intraventricular administration of human beta-endorphin (15 microgram) produced analgesia, hypothermia and catalepsy in male Sprague-Dawley rats.
  6. 06AnimalAnimal study (in vivo)Efficacy outcome

    In rats given repeated saline injections, multiple MIF injections did not alter beta-endorphin-induced hypothermia.

    In plain wordsIn rats given repeated saline injections, multiple MIF injections did not change the beta-endorphin-induced fall in body temperature.

    Peptide
    MIF-1 (Pro-Leu-Gly-NH2)
    Outcome
    No significant changeBeta-endorphin hypothermia without prior beta-endorphin exposure
    Study

    ratn: not reported in source

    Male Sprague-Dawley rats
    Outcome group
    Body temperature · Whole body
    Studied dose
    Dose not stated

    Source sentences

    Summary
    Multiple injections of MIF or cyclo(Leu-Gly) did not alter beta-endorphin-induced analgesia, catalepsy and hypothermia in rats which were given repeated intraventricular injections of saline.
    1 context sentence
    Summary · context
    Acute intraventricular administration of human beta-endorphin (15 microgram) produced analgesia, hypothermia and catalepsy in male Sprague-Dawley rats.

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.

  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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