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Study · Animal study (in vivo) · dog · 1995

10 results

Design and biological activities of L-163,191 (MK-0677): a potent, orally active growth hormone secretagogue.

Patchett AA, Nargund RP, Tata JR, Chen MH, Barakat KJ, Johnston DB, Cheng K, Chan WW, Butler B, Hickey G

Proceedings of the National Academy of Sciences of the United States of America1 Jul 1995Cited by 190 (Europe PMC)

PMID7624358 (opens in a new tab)PMCIDPMC41459 (opens in a new tab)DOI10.1073/pnas.92.15.7001 (opens in a new tab)PepBankPUB-07624358
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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 study10

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

  1. 01AnimalAnimal study (in vivo)Efficacy outcome

    In dogs, oral L-163,191 elevated GH at doses as low as 0.125 mg/kg.

    In plain wordsIn dogs, oral MK-0677 increased growth hormone levels.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    IncreaseGrowth hormone levels
    Study

    dogn: not reported in source

    Outcome group
    Growth hormone and IGF-1 · Endocrine and hormones
    Studied dose
    as low as 0.125 mg/kg · oralAs given in this study (dog).

    Source sentences

    Summary
    L-163,191 elevates GH in dogs after oral doses as low as 0.125 mg/kg and was shown to be specific in its release of GH without significant effect on plasma levels of aldosterone, luteinizing hormone, thyroxine, and prolactin after oral administration of 1 mg/kg.
  2. 02AnimalAnimal study (in vivo)Efficacy outcome

    In dogs, oral L-163,191 had no significant effect on plasma aldosterone.

    In plain wordsIn dogs, oral MK-0677 did not significantly change blood aldosterone levels.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    No significant changePlasma aldosterone
    Study

    dogn: not reported in source

    Outcome group
    Stress hormones · Endocrine and hormones
    Studied dose
    1 mg/kg · oralAs given in this study (dog).

    Source sentences

    Summary
    L-163,191 elevates GH in dogs after oral doses as low as 0.125 mg/kg and was shown to be specific in its release of GH without significant effect on plasma levels of aldosterone, luteinizing hormone, thyroxine, and prolactin after oral administration of 1 mg/kg.
  3. 03AnimalAnimal study (in vivo)Efficacy outcome

    In dogs, oral L-163,191 had no significant effect on plasma luteinizing hormone.

    In plain wordsIn dogs, oral MK-0677 did not significantly change blood luteinizing hormone levels.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    No significant changePlasma luteinizing hormone
    Study

    dogn: not reported in source

    Outcome group
    Sex hormones and fertility · Endocrine and hormones
    Studied dose
    1 mg/kg · oralAs given in this study (dog).

    Source sentences

    Summary
    L-163,191 elevates GH in dogs after oral doses as low as 0.125 mg/kg and was shown to be specific in its release of GH without significant effect on plasma levels of aldosterone, luteinizing hormone, thyroxine, and prolactin after oral administration of 1 mg/kg.
  4. 04AnimalAnimal study (in vivo)Efficacy outcome

    In dogs, oral L-163,191 had no significant effect on plasma thyroxine.

    In plain wordsIn dogs, oral MK-0677 did not significantly change blood thyroxine levels.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    No significant changePlasma thyroxine
    Study

    dogn: not reported in source

    Outcome group
    Thyroid function · Endocrine and hormones
    Studied dose
    1 mg/kg · oralAs given in this study (dog).

    Source sentences

    Summary
    L-163,191 elevates GH in dogs after oral doses as low as 0.125 mg/kg and was shown to be specific in its release of GH without significant effect on plasma levels of aldosterone, luteinizing hormone, thyroxine, and prolactin after oral administration of 1 mg/kg.
  5. 05AnimalAnimal study (in vivo)Efficacy outcome

    In dogs, oral L-163,191 had no significant effect on plasma prolactin.

    In plain wordsIn dogs, oral MK-0677 did not significantly change blood prolactin levels.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    No significant changePlasma prolactin
    Study

    dogn: not reported in source

    Outcome group
    Pituitary hormones · Endocrine and hormones
    Studied dose
    1 mg/kg · oralAs given in this study (dog).

    Source sentences

    Summary
    L-163,191 elevates GH in dogs after oral doses as low as 0.125 mg/kg and was shown to be specific in its release of GH without significant effect on plasma levels of aldosterone, luteinizing hormone, thyroxine, and prolactin after oral administration of 1 mg/kg.
  6. 06AnimalAnimal study (in vivo)Efficacy outcome

    In dogs, L-163,191 produced only modest increases in cortisol.

    In plain wordsIn dogs, MK-0677 produced only modest increases in cortisol.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    IncreaseCortisol
    Study

    dogn: not reported in source

    Outcome group
    Stress hormones · Endocrine and hormones
    Studied dose
    Dose not stated · oralAs given in this study (dog).

    Source sentences

    Summary
    Only modest increases in cortisol were observed.
    1 context sentence
    Summary · context
    L-163,191 elevates GH in dogs after oral doses as low as 0.125 mg/kg and was shown to be specific in its release of GH without significant effect on plasma levels of aldosterone, luteinizing hormone, thyroxine, and prolactin after oral administration of 1 mg/kg.
  7. 07LabIn vitro (cells)Efficacy outcome

    In cultured rat pituitary cells, L-163,191 released GH with EC50 = 1.3 +/- 0.09 nM.

    In plain wordsIn cells, MK-0677 stimulated growth hormone release from rat pituitary cells.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    IncreaseGrowth hormone release EC50
    Study

    ratn: not reported in source

    cultured pituitary cells
    Outcome group
    Growth hormone and IGF-1 · Endocrine and hormones
    Studied dose
    Dose not stated

    Measurements

    EC50
    1.3 nM
    GH release in cultured rat pituitary cells

    Source sentences

    Summary
    L-163,191 releases GH from rat pituitary cells in culture with EC50 = 1.3 +/- 0.09 nM and is mechanistically indistinguishable from the GH-releasing peptide GHRP-6 and the prototypical nonpeptide GH secretagogue L-692,429 but clearly distinguishable from the natural GH secretagogue, GH-releasing hormone.
  8. 08LabIn vitro (cells)Mechanism

    In cultured rat pituitary cells, L-163,191 was mechanistically indistinguishable from GHRP-6.

    In plain wordsIn cells, MK-0677 acted through the same reported mechanism as GHRP-6 in rat pituitary cells.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    No significant changeMechanism relative to GHRP-6
    Study

    ratn: not reported in source

    cultured pituitary cells
    Comparator
    GHRP-6
    Outcome group
    Receptor activity and mechanism · Pharmacology
    Studied dose
    Dose not stated

    Source sentences

    Summary
    L-163,191 releases GH from rat pituitary cells in culture with EC50 = 1.3 +/- 0.09 nM and is mechanistically indistinguishable from the GH-releasing peptide GHRP-6 and the prototypical nonpeptide GH secretagogue L-692,429 but clearly distinguishable from the natural GH secretagogue, GH-releasing hormone.
  9. 09LabIn vitro (cells)Mechanism

    In cultured rat pituitary cells, L-163,191 was mechanistically indistinguishable from L-692,429.

    In plain wordsIn cells, MK-0677 acted through the same reported mechanism as L-692,429 in rat pituitary cells.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    No significant changeMechanism relative to L-692,429
    Study

    ratn: not reported in source

    cultured pituitary cells
    Comparator
    L-692,429
    Outcome group
    Receptor activity and mechanism · Pharmacology
    Studied dose
    Dose not stated

    Source sentences

    Summary
    L-163,191 releases GH from rat pituitary cells in culture with EC50 = 1.3 +/- 0.09 nM and is mechanistically indistinguishable from the GH-releasing peptide GHRP-6 and the prototypical nonpeptide GH secretagogue L-692,429 but clearly distinguishable from the natural GH secretagogue, GH-releasing hormone.
  10. 10LabIn vitro (cells)Mechanism

    In cultured rat pituitary cells, L-163,191 was mechanistically distinguishable from GH-releasing hormone.

    In plain wordsIn cells, MK-0677 acted differently from growth hormone-releasing hormone in rat pituitary cells.

    Peptide
    MK-677 (ibutamoren)
    Outcome
    Not applicableMechanism relative to GH-releasing hormone
    Study

    ratn: not reported in source

    cultured pituitary cells
    Comparator
    GH-releasing hormone
    Outcome group
    Receptor activity and mechanism · Pharmacology
    Studied dose
    Dose not stated

    Source sentences

    Summary
    L-163,191 releases GH from rat pituitary cells in culture with EC50 = 1.3 +/- 0.09 nM and is mechanistically indistinguishable from the GH-releasing peptide GHRP-6 and the prototypical nonpeptide GH secretagogue L-692,429 but clearly distinguishable from the natural GH secretagogue, GH-releasing hormone.

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. Versions 4 to 14Current

    28 Oct 2026, 02:02 UTC

    The same notice was added 11 times, first on 14 Oct 2026, 05:02 UTC. The status did not change between them.

    Study results updated

  2. Version 3

    14 Oct 2026, 01:46 UTC

    Study data updated · source update from Europe PMC

  3. Version 2

    12 Oct 2026, 12:58 UTC

    Study results updated

  4. Version 1

    9 Oct 2026, 03:13 UTC

    First added · source update from Europe PMC

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