Skip to content

Study · Animal study (in vivo) · rat · 2002

13 results

Growth hormone (GH) and GH-releasing peptide-6 increase brain insulin-like growth factor-I expression and activate intracellular signaling pathways involved in neuroprotection.

Frago LM, Pañeda C, Dickson SL, Hewson AK, Argente J, Chowen JA

Endocrinology1 Oct 2002Cited by 93 (Europe PMC)

PMID12239123 (opens in a new tab)DOI10.1210/en.2002-220261 (opens in a new tab)PepBankPUB-12239123
Source linkPubMedAsk about this study
Jump to 13 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 study13

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

  1. 01AnimalAnimal study (in vivo)Mechanism

    In adult male rats, GHRP‑6 increased hypothalamic IGF-I mRNA.

    In plain wordsIn rats, GHRP‑6 increased IGF-I gene expression in the hypothalamus.

    Peptide
    GHRP-6
    Outcome
    IncreaseHypothalamic IGF-I mRNA
    Study

    ratsn: not reported in source

    Adult male rats
    Outcome group
    Neuroprotection · Nervous system and cognition
    Studied dose
    Dose not stated · 1 weekAs given in this study (rats).

    Source sentences

    Summary
    Treatment of adult male rats with GHRP-6 or GH for 1 wk significantly increased IGF-I mRNA levels in the hypothalamus, cerebellum, and hippocampus, with no effect in cerebral cortex.
  2. 02AnimalAnimal study (in vivo)Mechanism

    In adult male rats, GHRP‑6 increased cerebellar IGF-I mRNA.

    In plain wordsIn rats, GHRP‑6 increased IGF-I gene expression in the cerebellum.

    Peptide
    GHRP-6
    Outcome
    IncreaseCerebellar IGF-I mRNA
    Study

    ratsn: not reported in source

    Adult male rats
    Outcome group
    Neuroprotection · Nervous system and cognition
    Studied dose
    Dose not stated · 1 weekAs given in this study (rats).

    Source sentences

    Summary
    Treatment of adult male rats with GHRP-6 or GH for 1 wk significantly increased IGF-I mRNA levels in the hypothalamus, cerebellum, and hippocampus, with no effect in cerebral cortex.
  3. 03AnimalAnimal study (in vivo)Mechanism

    In adult male rats, GHRP‑6 increased hippocampal IGF-I mRNA.

    In plain wordsIn rats, GHRP‑6 increased IGF-I gene expression in the hippocampus.

    Peptide
    GHRP-6
    Outcome
    IncreaseHippocampal IGF-I mRNA
    Study

    ratsn: not reported in source

    Adult male rats
    Outcome group
    Neuroprotection · Nervous system and cognition
    Studied dose
    Dose not stated · 1 weekAs given in this study (rats).

    Source sentences

    Summary
    Treatment of adult male rats with GHRP-6 or GH for 1 wk significantly increased IGF-I mRNA levels in the hypothalamus, cerebellum, and hippocampus, with no effect in cerebral cortex.
  4. 04AnimalAnimal study (in vivo)Mechanism

    In adult male rats, GHRP‑6 did not affect cerebral cortex IGF-I mRNA.

    In plain wordsIn rats, GHRP‑6 did not change IGF-I gene expression in the cerebral cortex.

    Peptide
    GHRP-6
    Outcome
    No significant changeCortical IGF-I mRNA
    Study

    ratsn: not reported in source

    Adult male rats
    Outcome group
    Neuroprotection · Nervous system and cognition
    Studied dose
    Dose not stated · 1 weekAs given in this study (rats).

    Source sentences

    Summary
    Treatment of adult male rats with GHRP-6 or GH for 1 wk significantly increased IGF-I mRNA levels in the hypothalamus, cerebellum, and hippocampus, with no effect in cerebral cortex.
  5. 05AnimalAnimal study (in vivo)Mechanism

    In adult male rats, GHRP‑6 did not affect IGF receptor expression.

    In plain wordsIn rats, GHRP‑6 did not change IGF receptor expression.

    Peptide
    GHRP-6
    Outcome
    No significant changeIGF receptor expression
    Study

    ratsn: not reported in source

    Adult male rats
    Outcome group
    Neuroprotection · Nervous system and cognition
    Studied dose
    Dose not stated · 1 weekAs given in this study (rats).

    Source sentences

    Summary
    Expression of the IGF receptor and IGF-binding protein (IGFBP)-2 were not affected.
    1 context sentence
    Summary · context
    Treatment of adult male rats with GHRP-6 or GH for 1 wk significantly increased IGF-I mRNA levels in the hypothalamus, cerebellum, and hippocampus, with no effect in cerebral cortex.
  6. 06AnimalAnimal study (in vivo)Mechanism

    In adult male rats, GHRP‑6 did not affect IGFBP-2 expression.

    In plain wordsIn rats, GHRP‑6 did not change IGFBP-2 expression.

    Peptide
    GHRP-6
    Outcome
    No significant changeIGFBP-2 expression
    Study

    ratsn: not reported in source

    Adult male rats
    Outcome group
    Neuroprotection · Nervous system and cognition
    Studied dose
    Dose not stated · 1 weekAs given in this study (rats).

    Source sentences

    Summary
    Expression of the IGF receptor and IGF-binding protein (IGFBP)-2 were not affected.
    1 context sentence
    Summary · context
    Treatment of adult male rats with GHRP-6 or GH for 1 wk significantly increased IGF-I mRNA levels in the hypothalamus, cerebellum, and hippocampus, with no effect in cerebral cortex.
  7. 07AnimalAnimal study (in vivo)Mechanism

    In adult male rats, GHRP‑6 stimulated Akt phosphorylation where IGF-I increased.

    In plain wordsIn rats, GHRP‑6 increased Akt phosphorylation in brain areas where IGF-I increased.

    Peptide
    GHRP-6
    Outcome
    IncreaseAkt phosphorylation
    Study

    ratsn: not reported in source

    Adult male rats
    Outcome group
    Neuroprotection · Nervous system and cognition
    Studied dose
    Dose not stated · 1 weekAs given in this study (rats).

    Source sentences

    Summary
    Phosphorylation of Akt and Bad was stimulated in areas where IGF-I was increased, with no change in MAPK or glycogen synthase kinase-3beta.
    1 context sentence
    Summary · context
    Treatment of adult male rats with GHRP-6 or GH for 1 wk significantly increased IGF-I mRNA levels in the hypothalamus, cerebellum, and hippocampus, with no effect in cerebral cortex.
  8. 08AnimalAnimal study (in vivo)Mechanism

    In adult male rats, GHRP‑6 stimulated Bad phosphorylation where IGF-I increased.

    In plain wordsIn rats, GHRP‑6 increased Bad phosphorylation in brain areas where IGF-I increased.

    Peptide
    GHRP-6
    Outcome
    IncreaseBad phosphorylation
    Study

    ratsn: not reported in source

    Adult male rats
    Outcome group
    Neuroprotection · Nervous system and cognition
    Studied dose
    Dose not stated · 1 weekAs given in this study (rats).

    Source sentences

    Summary
    Phosphorylation of Akt and Bad was stimulated in areas where IGF-I was increased, with no change in MAPK or glycogen synthase kinase-3beta.
    1 context sentence
    Summary · context
    Treatment of adult male rats with GHRP-6 or GH for 1 wk significantly increased IGF-I mRNA levels in the hypothalamus, cerebellum, and hippocampus, with no effect in cerebral cortex.
  9. 09AnimalAnimal study (in vivo)Mechanism

    In adult male rats, GHRP‑6 did not change MAPK in regions where IGF-I increased.

    In plain wordsIn rats, GHRP‑6 did not change MAPK in brain regions where IGF-I increased.

    Peptide
    GHRP-6
    Outcome
    No significant changeMAPK
    Study

    ratsn: not reported in source

    Adult male rats
    Outcome group
    Neuroprotection · Nervous system and cognition
    Studied dose
    Dose not stated · 1 weekAs given in this study (rats).

    Source sentences

    Summary
    Phosphorylation of Akt and Bad was stimulated in areas where IGF-I was increased, with no change in MAPK or glycogen synthase kinase-3beta.
    1 context sentence
    Summary · context
    Treatment of adult male rats with GHRP-6 or GH for 1 wk significantly increased IGF-I mRNA levels in the hypothalamus, cerebellum, and hippocampus, with no effect in cerebral cortex.
  10. 10AnimalAnimal study (in vivo)Mechanism

    In adult male rats, GHRP‑6 did not change glycogen synthase kinase-3beta in regions where IGF-I increased.

    In plain wordsIn rats, GHRP‑6 did not change glycogen synthase kinase-3beta in brain regions where IGF-I increased.

    Peptide
    GHRP-6
    Outcome
    No significant changeGlycogen synthase kinase-3beta
    Study

    ratsn: not reported in source

    Adult male rats
    Outcome group
    Neuroprotection · Nervous system and cognition
    Studied dose
    Dose not stated · 1 weekAs given in this study (rats).

    Source sentences

    Summary
    Phosphorylation of Akt and Bad was stimulated in areas where IGF-I was increased, with no change in MAPK or glycogen synthase kinase-3beta.
    1 context sentence
    Summary · context
    Treatment of adult male rats with GHRP-6 or GH for 1 wk significantly increased IGF-I mRNA levels in the hypothalamus, cerebellum, and hippocampus, with no effect in cerebral cortex.
  11. 11AnimalAnimal study (in vivo)Mechanism

    In adult male rats, GHRP‑6 increased Bcl-2 in brain regions where IGF-I increased.

    In plain wordsIn rats, GHRP‑6 increased Bcl-2 in brain regions where IGF-I increased.

    Peptide
    GHRP-6
    Outcome
    IncreaseBcl-2
    Study

    ratsn: not reported in source

    Adult male rats
    Outcome group
    Neuroprotection · Nervous system and cognition
    Studied dose
    Dose not stated · 1 weekAs given in this study (rats).

    Source sentences

    Summary
    Indeed, the antiapoptotic protein Bcl-2 was augmented in these same areas, with no change in the proapoptotic protein Bax.
    1 context sentence
    Summary · context
    Treatment of adult male rats with GHRP-6 or GH for 1 wk significantly increased IGF-I mRNA levels in the hypothalamus, cerebellum, and hippocampus, with no effect in cerebral cortex.
  12. 12AnimalAnimal study (in vivo)Mechanism

    In adult male rats, GHRP‑6 did not change Bax in brain regions where IGF-I increased.

    In plain wordsIn rats, GHRP‑6 did not change Bax in brain regions where IGF-I increased.

    Peptide
    GHRP-6
    Outcome
    No significant changeBax
    Study

    ratsn: not reported in source

    Adult male rats
    Outcome group
    Neuroprotection · Nervous system and cognition
    Studied dose
    Dose not stated · 1 weekAs given in this study (rats).

    Source sentences

    Summary
    Indeed, the antiapoptotic protein Bcl-2 was augmented in these same areas, with no change in the proapoptotic protein Bax.
    1 context sentence
    Summary · context
    Treatment of adult male rats with GHRP-6 or GH for 1 wk significantly increased IGF-I mRNA levels in the hypothalamus, cerebellum, and hippocampus, with no effect in cerebral cortex.
  13. 13AnimalAnimal study (in vivo)Mechanism

    In adult male rats, GHRP‑6 increased IGFBP-5 mainly in the hypothalamus.

    In plain wordsIn rats, GHRP‑6 increased IGFBP-5 mainly in the hypothalamus.

    Peptide
    GHRP-6
    Outcome
    IncreaseIGFBP-5
    Study

    ratsn: not reported in source

    Adult male rats
    Outcome group
    Neuroprotection · Nervous system and cognition
    Studied dose
    Dose not stated · 1 weekAs given in this study (rats).

    Source sentences

    Summary
    IGFBP-5, also reported to be involved in neuron survival processes, was increased mainly in the hypothalamus, suggesting a possible neuroendocrine role.
    1 context sentence
    Summary · context
    Treatment of adult male rats with GHRP-6 or GH for 1 wk significantly increased IGF-I mRNA levels in the hypothalamus, cerebellum, and hippocampus, with no effect in cerebral cortex.

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, 15:58 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.