On the actions of the growth hormone-releasing hexapeptide, GHRP.

Bowers CY, Sartor AO, Reynolds GA, Badger TM

Endocrinology1 Apr 1991Cited by 156 (Europe PMC)

PMID2004615DOI10.1210/endo-128-4-2027PepBankPUB-02004615

Publisher page PubMedAsk about this study

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 study7

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

01AnimalAnimal study (in vivo)Mechanism
In rats, GHRP did not inhibit somatostatin release, unlike the opiates tested.
In plain wordsIn rats, GHRP did not inhibit somatostatin release, unlike the tested opiates.
Peptide
GHRP-6
Outcome
No significant changeSomatostatin release
Study
ratn: not reported in source
rats
Outcome group
Growth hormone and IGF-1 · Endocrine and hormones
Studied dose
Dose not stated
Source sentences
Summary
Present data indicate that one of the major differences in the actions of dermorphin, 2549, and GHRP is the inhibition of somatostatin (SRIF) release by the opiates but not by GHRP.
1 context sentence(design, population, supporting numbers)
Summary · context
These effects are mediated via non-GH-releasing hormone (non-GHRH) and nonopiate receptors in rats.
Report a problemFND-0200461503

Studies that did not test the peptide alone6

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.

02AnimalNot a test of GHRP-6 aloneAnimal study (in vivo)Mechanism
In rats, GHRP co-administered with dermorphin synergistically released GH.
In plain wordsIn rats, GHRP with dermorphin produced synergistic GH release.
Peptide
GHRP-6
Outcome
IncreaseGH synergy with dermorphin
Study
ratn: not reported in source
rats
Outcome group
Growth hormone and IGF-1 · Endocrine and hormones
Source sentences
Summary
Evidence indicates that these opiates and GHRP administered together synergistically release GH, demonstrating the independent action(s) of GHRP and the opiates.
1 context sentence(design, population, supporting numbers)
Summary · context
Select types of opiates are known to release GH by a hypothalamic site of action, and thus, the dermorphin heptapeptide and benzomorphan opiate agonist 2549 used in this study presumably act on the hypothalamus to release GH.
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.
Report a problemFND-0200461501
03AnimalNot a test of GHRP-6 aloneAnimal study (in vivo)Mechanism
In rats, GHRP co-administered with 2549 synergistically released GH.
In plain wordsIn rats, GHRP with 2549 produced synergistic GH release.
Peptide
GHRP-6
Outcome
IncreaseGH synergy with 2549
Study
ratn: not reported in source
rats
Outcome group
Growth hormone and IGF-1 · Endocrine and hormones
Source sentences
Summary
Evidence indicates that these opiates and GHRP administered together synergistically release GH, demonstrating the independent action(s) of GHRP and the opiates.
1 context sentence(design, population, supporting numbers)
Summary · context
Select types of opiates are known to release GH by a hypothalamic site of action, and thus, the dermorphin heptapeptide and benzomorphan opiate agonist 2549 used in this study presumably act on the hypothalamus to release GH.
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.
Report a problemFND-0200461502
04AnimalNot a test of GHRP-6 aloneAnimal study (in vivo)Mechanism
In rats, GHRP with GHRH and dermorphin showed a synergistic interaction in GH release.
In plain wordsIn rats, GHRP with GHRH and dermorphin produced synergistic GH release.
Peptide
GHRP-6
Outcome
IncreaseTriple combination GH synergy with dermorphin
Study
ratn: not reported in source
rats
Outcome group
Growth hormone and IGF-1 · Endocrine and hormones
Source sentences
Summary
The complementary, rather dramatic synergistic interaction of GHRP, GHRH, and dermorphin or GHRP, GHRH, and 2549 in releasing GH again strongly supports the independent actions of these compounds.
1 context sentence(design, population, supporting numbers)
Summary · context
These effects are mediated via non-GH-releasing hormone (non-GHRH) and nonopiate receptors in rats.
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.
Report a problemFND-0200461504
05AnimalNot a test of GHRP-6 aloneAnimal study (in vivo)Mechanism
In rats, GHRP with GHRH and 2549 showed a synergistic interaction in GH release.
In plain wordsIn rats, GHRP with GHRH and 2549 produced synergistic GH release.
Peptide
GHRP-6
Outcome
IncreaseTriple combination GH synergy with 2549
Study
ratn: not reported in source
rats
Outcome group
Growth hormone and IGF-1 · Endocrine and hormones
Source sentences
Summary
The complementary, rather dramatic synergistic interaction of GHRP, GHRH, and dermorphin or GHRP, GHRH, and 2549 in releasing GH again strongly supports the independent actions of these compounds.
1 context sentence(design, population, supporting numbers)
Summary · context
These effects are mediated via non-GH-releasing hormone (non-GHRH) and nonopiate receptors in rats.
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.
Report a problemFND-0200461505
06LabNot a test of GHRP-6 aloneIn vitro (cells)Mechanism
In vitro, dermorphin did not augment the direct pituitary GH response to GHRP.
In plain wordsIn lab tests, dermorphin did not increase the pituitary GH response to GHRP.
Peptide
GHRP-6
Outcome
No significant changeDermorphin augmentation of GHRP response
Study
ratn: not reported in source
pituitary in vitro system
Outcome group
Growth hormone and IGF-1 · Endocrine and hormones
Source sentences
Summary
Neither dermorphin nor 2549 released GH or augmented the GH responses of GHRP or GHRH in vitro by a direct pituitary action, while GHRH antiserum inhibited the GH response of both dermorphin and 2549 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.
Report a problemFND-0200461506
07LabNot a test of GHRP-6 aloneIn vitro (cells)Mechanism
In vitro, 2549 did not augment the direct pituitary GH response to GHRP.
In plain wordsIn lab tests, 2549 did not increase the pituitary GH response to GHRP.
Peptide
GHRP-6
Outcome
No significant change2549 augmentation of GHRP response
Study
ratn: not reported in source
pituitary in vitro system
Outcome group
Growth hormone and IGF-1 · Endocrine and hormones
Source sentences
Summary
Neither dermorphin nor 2549 released GH or augmented the GH responses of GHRP or GHRH in vitro by a direct pituitary action, while GHRH antiserum inhibited the GH response of both dermorphin and 2549 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.
Report a problemFND-0200461507

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.

Version 2Current
21 Oct 2026, 15:59 UTC
Study results updated
Version 1
9 Oct 2026, 03:13 UTC
First added · source update from Europe PMC

Subjects

Terms as the source lists them.

Publication types

MeSH terms

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