Skip to content

Study · Animal study (in vivo) · rat · 1992

12 results

Role of selected endogenous peptides in growth hormone-releasing hexapeptide activity: analysis of growth hormone-releasing hormone, thyroid hormone-releasing hormone, and gonadotropin-releasing hormone.

Bercu BB, Yang SW, Masuda R, Walker RF

Endocrinology1 May 1992Cited by 18 (Europe PMC)

PMID1315249 (opens in a new tab)DOI10.1210/endo.130.5.1315249 (opens in a new tab)PepBankPUB-01315249
Source linkPubMedAsk about this study
Jump to 12 results

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 study12

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

  1. 01AnimalAnimal study (in vivo)Mechanism

    In hypothyroid rats, a subthreshold GHRP‑6 dose was more effective than in euthyroid rats.

    In plain wordsIn rats, a low GHRP‑6 dose was more effective with low thyroid function than with normal thyroid function.

    Peptide
    GHRP-6
    Outcome
    IncreaseSubthreshold dose activity in hypothyroidism
    Study

    ratn: not reported in source

    Comparator
    Euthyroid rats
    Outcome group
    Growth hormone and IGF-1 · Endocrine and hormones
    Studied dose
    Subthreshold doseAs given in this study (rat).

    Source sentences

    Summary
    Like TRH, a subthreshold dose of GHRP-6 was significantly more effective in hypothyroid rats than in euthyroid rats.
  2. 02AnimalAnimal study (in vivo)Mechanism

    In hypothyroid rats, suprathreshold GHRP‑6 doses were less effective than in euthyroid rats.

    In plain wordsIn rats, higher GHRP‑6 doses were less effective with low thyroid function than with normal thyroid function.

    Peptide
    GHRP-6
    Outcome
    DecreaseSuprathreshold dose activity in hypothyroidism
    Study

    ratn: not reported in source

    Comparator
    Euthyroid rats
    Outcome group
    Growth hormone and IGF-1 · Endocrine and hormones
    Studied dose
    Suprathreshold dosesAs given in this study (rat).

    Source sentences

    Summary
    However, suprathreshold doses of GHRP-6 were less effective in hypothyroid rats.
    1 context sentence
    Summary · context
    Like TRH, a subthreshold dose of GHRP-6 was significantly more effective in hypothyroid rats than in euthyroid rats.
  3. 03LabIn vitro (cells)Mechanism

    In GH3 cells, GHRP‑6 had no effect on GH release.

    In plain wordsIn cells, GHRP‑6 did not change growth hormone release.

    Peptide
    GHRP-6
    Outcome
    No significant changeGH release
    Study

    n: not reported in source

    GH3 cells
    Outcome group
    Growth hormone and IGF-1 · Endocrine and hormones
    Studied dose
    Dose not stated

    Source sentences

    Summary
    Unlike TRH, GHRP-6 had no effect on GH and prolactin release from GH3 cells,
  4. 04LabIn vitro (cells)Mechanism

    In GH3 cells, GHRP‑6 had no effect on prolactin release.

    In plain wordsIn cells, GHRP‑6 did not change prolactin release.

    Peptide
    GHRP-6
    Outcome
    No significant changeProlactin release
    Study

    n: not reported in source

    GH3 cells
    Outcome group
    Growth hormone and IGF-1 · Endocrine and hormones
    Studied dose
    Dose not stated

    Source sentences

    Summary
    Unlike TRH, GHRP-6 had no effect on GH and prolactin release from GH3 cells,

Studies that did not test the peptide alone8

In this study, GHRP-6 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 GHRP-6.

  1. 05AnimalNot a test of GHRP-6 aloneAnimal study (in vivo)Mechanism

    In rats, GHRH antiserum attenuated GHRP‑6 activity.

    In plain wordsIn rats, GHRH antiserum reduced GHRP‑6 activity.

    Peptide
    GHRP-6
    Outcome
    DecreaseGHRH antiserum-modified activity
    Study

    ratn: not reported in source

    Outcome group
    Growth hormone and IGF-1 · Endocrine and hormones

    Source sentences

    Summary
    The activity of GHRP-6, a synthetic GH secretagogue, was significantly attenuated in rats administered GHRH antiserum or alpha-methyl-rho-tyrosine to reduce endogenous GHRH concentrations, and also in rats administered 5-50 micrograms/kg of [N-Ac-Tyr1,D-Arg2]-GRF 1-29 amide to block pituitary GHRH receptors.

    In this study, GHRP-6 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 GHRP-6.

  2. 06AnimalNot a test of GHRP-6 aloneAnimal study (in vivo)Mechanism

    In rats, alpha-methyl-rho-tyrosine attenuated GHRP‑6 activity.

    In plain wordsIn rats, alpha-methyl-rho-tyrosine reduced GHRP‑6 activity.

    Peptide
    GHRP-6
    Outcome
    DecreaseAlpha-methyl-rho-tyrosine-modified activity
    Study

    ratn: not reported in source

    Outcome group
    Growth hormone and IGF-1 · Endocrine and hormones

    Source sentences

    Summary
    The activity of GHRP-6, a synthetic GH secretagogue, was significantly attenuated in rats administered GHRH antiserum or alpha-methyl-rho-tyrosine to reduce endogenous GHRH concentrations, and also in rats administered 5-50 micrograms/kg of [N-Ac-Tyr1,D-Arg2]-GRF 1-29 amide to block pituitary GHRH receptors.

    In this study, GHRP-6 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 GHRP-6.

  3. 07AnimalNot a test of GHRP-6 aloneAnimal study (in vivo)Mechanism

    In rats, the GHRH receptor antagonist at 5-50 micrograms/kg attenuated GHRP‑6 activity.

    In plain wordsIn rats, the GHRH receptor antagonist at 5-50 micrograms/kg reduced GHRP‑6 activity.

    Peptide
    GHRP-6
    Outcome
    DecreaseLow-dose GHRH antagonist-modified activity
    Study

    ratn: not reported in source

    Outcome group
    Growth hormone and IGF-1 · Endocrine and hormones

    Source sentences

    Summary
    The activity of GHRP-6, a synthetic GH secretagogue, was significantly attenuated in rats administered GHRH antiserum or alpha-methyl-rho-tyrosine to reduce endogenous GHRH concentrations, and also in rats administered 5-50 micrograms/kg of [N-Ac-Tyr1,D-Arg2]-GRF 1-29 amide to block pituitary GHRH receptors.

    In this study, GHRP-6 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 GHRP-6.

  4. 08AnimalNot a test of GHRP-6 aloneAnimal study (in vivo)Mechanism

    In rats, the GHRH receptor antagonist at 150 micrograms/kg potentiated GHRP‑6 activity.

    In plain wordsIn rats, the GHRH receptor antagonist at 150 micrograms/kg increased GHRP‑6 activity.

    Peptide
    GHRP-6
    Outcome
    IncreaseHigh-dose GHRH antagonist-modified activity
    Study

    ratn: not reported in source

    Outcome group
    Growth hormone and IGF-1 · Endocrine and hormones

    Source sentences

    Summary
    However, GHRP-6 activity was potentiated in rats administered 150 micrograms/kg [N-Ac-Tyr1,D-Arg2]-GRF 1-29 amide, presumably due to partial agonist activity of the GHRH receptor antagonist at the higher dose.

    In this study, GHRP-6 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 GHRP-6.

  5. 09AnimalNot a test of GHRP-6 aloneAnimal study (in vivo)Mechanism

    In rats, a GnRH receptor antagonist did not block GHRP‑6 activity.

    In plain wordsIn rats, a GnRH receptor antagonist did not block GHRP‑6 activity.

    Peptide
    GHRP-6
    Outcome
    No significant changeGnRH antagonist-modified activity
    Study

    ratn: not reported in source

    Outcome group
    Growth hormone and IGF-1 · Endocrine and hormones

    Source sentences

    Summary
    A GnRH receptor antagonist did not block GHRP-6 activity in vivo,

    In this study, GHRP-6 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 GHRP-6.

  6. 10AnimalNot a test of GHRP-6 aloneAnimal study (in vivo)Mechanism

    In rats, GnRH alone or combined with GHRP‑6 did not stimulate GH release.

    In plain wordsIn rats, GnRH alone or combined with GHRP‑6 did not stimulate growth hormone release.

    Peptide
    GHRP-6
    Outcome
    No significant changeGH release with GnRH
    Study

    ratn: not reported in source

    Outcome group
    Growth hormone and IGF-1 · Endocrine and hormones

    Source sentences

    Summary
    A GnRH receptor antagonist did not block GHRP-6 activity in vivo, and GnRH administered alone or in combination with GHRP-6, did not stimulate GH release.

    In this study, GHRP-6 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 GHRP-6.

  7. 11LabNot a test of GHRP-6 aloneIn vitro (cell-free)Mechanism

    In pituitary membranes, TRH poorly competed for radiolabeled GHRP‑6 binding sites.

    In plain wordsIn lab tests, TRH competed poorly for GHRP‑6 binding sites on pituitary membranes.

    Peptide
    GHRP-6
    Outcome
    Not applicableTRH competition for binding sites
    Study

    n: not reported in source

    Pituitary membranes
    Outcome group
    Growth hormone and IGF-1 · Endocrine and hormones

    Source sentences

    Summary
    and TRH and GnRH were poor competitors for 3H-GHRP-6 binding sites on pituitary membranes.

    In this study, GHRP-6 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 GHRP-6.

  8. 12LabNot a test of GHRP-6 aloneIn vitro (cell-free)Mechanism

    In pituitary membranes, GnRH poorly competed for radiolabeled GHRP‑6 binding sites.

    In plain wordsIn lab tests, GnRH competed poorly for GHRP‑6 binding sites on pituitary membranes.

    Peptide
    GHRP-6
    Outcome
    Not applicableGnRH competition for binding sites
    Study

    n: not reported in source

    Pituitary membranes
    Outcome group
    Growth hormone and IGF-1 · Endocrine and hormones

    Source sentences

    Summary
    and TRH and GnRH were poor competitors for 3H-GHRP-6 binding sites on pituitary membranes.

    In this study, GHRP-6 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 GHRP-6.

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

    21 Oct 2026, 15:59 UTC

    Study results updated

  2. Version 1

    9 Oct 2026, 03:13 UTC

    First added · source update from Europe PMC

Subjects

Terms as the source lists them.

PepBank is a research reference. Talk to a doctor before you use any peptide.