Please Read our Disclaimer

In this article, we will review the growth hormone-releasing peptides ipamorelin and GHRP-6. They have many similarities and a few differences. We aim to help you decide which peptide you need for your research. They are both available for sale at Loti Labs, which is a USA based peptide and research company.

A BRIEF INTRODUCTION OF GHRPs

Growth hormone-releasing peptides GHRPs are synthetic, non-natural peptides equipped with potent stimulatory effects on Growth hormone secretion in animal test subjects. They have no structural resemblance with Growth Hormone-Releasing Hormone and act through specific receptors present either at the pituitary or hypothalamic level in animals. The GH-releasing activity of GHRPs is noticeable and dose-related after intravenous subcutaneous intranasal and oral administration.

The Growth Hormone Releasing Peptides are affected by glucose, free fatty acids, glucocorticoids, and somatostatin.

Ipamorelin is a third-generation GHRP after GHRP-6, which belongs to the first generation to be extensively studied in animals. It is similar to GHRP-6 because they both release GH at similar rates without the side effects that GHRP-6 exhibits. GHRP-6 causes a release, and an increase in cortisol and prolactin levels, however, ipamorelin only selectively releases GH.

STRUCTURAL DIFFERENCES BETWEEN GHRP6 AND IPAMORELIN

DIFFERENCES	GHRP 6	IPAMORELIN
STRUCTURE
AMINO ACID SEQUENCE	His-D-Trp-Ala-Trp-D-Phe-Lys-NH2	H-Aib-His-D-2Nal-D-Phe-Lys-NH2
MOLECULAR FORMULA	C46H56N12O6	C38H49N9O5
MOLECULAR WEIGHT	873 g/mol	711.9 g/mol

MECHANISM OF ACTION

Studies in animal test subjects show that both GHRP-6 and ipamorelin stimulate Ghrelin, “the hunger hormone” through its ghrelin receptor which in turn signal an increased production of growth hormone (GH) by acting at the level of the pituitary or hypothalamus through a specific receptor different from that of the endogenous Growth Hormone-Releasing Hormone GHRH. The effects of GHRP-6 on GH release were achieved using various doses and administration routes.

Іn соntrаѕt tо GHRP-6, Iраmоrеlіn іѕ mоrе ѕеlесtіvе іn іtѕ асtіvаtіоn because it doesn’t have any effect on cortisol or prolactin. It іѕ mеtаbоlіzеd ѕlоwеr thаn GHRP-6, mаkіng іt mоrе ѕtаblе аnd thеrеbу еffесtіvе fоr lоngеr.

COMPARING AND CONTRASTING THE EFFECTS OF IPAMORELIN AND GHRP-6

Ipamorelin and GHRP-6 have similar effects on animal test subjects but differ structurally. They both act on the pituitary gland to release growth hormone. Their differences are listed in the table below.

	GHRP-6	IPAMORELIN
Effect on hunger	Increases hunger markedly	Doesn’t promote hunger
Effect on growth hormone release	More	Less
Effect on prolactin and cortisol release	Less control	None observed
Potency	Same	Same
Half-life	Shorter half-life	Longer half-life

CONCLUSION

GHRP-6 is one of the first GHRPs synthesized, and is widely considered to be the most effective of the growth hormone-releasing peptides, but the choice between GHRP-6 and ipamorelin depends on the outcome you want to achieve. Whatever your choice is, Loti Labs assures you of the highest quality USA-made peptides.

LOOKING FOR WHERE TO BUY PEPTIDES

Ipamorelin and GHRP-6 can both be purchased from Loti Labs. It is important to buy peptides that are USA-made for the integrity of your research. Ipamorelin and GHRP-6 sold from Loti Labs are tested through HPLC and Mass spectrometry to ensure quality. Ipamorelin and GHRP-6 are available in lyophilized powder form in 2mg and 5mg vials, respectively. Buy your peptides from is today!

References:

1. Camanni, Franco & Ghigo, Ezio & Arvat, Emanuela. (1998). Growth Hormone-Releasing Peptides and Their Analogs. Frontiers in neuroendocrinology. 19. 47-72. 10.1006/frne.1997.0158.

1. Wu D, Chen C, Zhang J, Bowers CY, Clarke IJ. The effects of GH-releasing peptide-6 (GHRP-6) and GHRP-2 on intracellular adenosine 3′,5′-monophosphate (cAMP) levels and GH secretion in ovine and rat somatotrophs. J Endocrinol. 1996;148(2):197–205. doi:10.1677/joe.0.1480197

1. Rogério G. Gondo, Manuel H. Aguiar-Oliveira, César Y. Hayashida, Sergio P. A. Toledo, Neusa Abelin, Michael A. Levine, Cyril Y. Bowers, Anita H. O. Souza, Rossana M. C. Pereira, Norma L. Santos, Roberto Salvatori, Growth Hormone-Releasing Peptide-2 Stimulates GH Secretion in GH-Deficient Patients with Mutated GH-Releasing Hormone Receptor, The Journal of Clinical Endocrinology & Metabolism, Volume 86, Issue 7, 1 July 2001, Pages 3279–3283, https://doi.org/10.1210/jcem.86.7.7694

1. Raun K, Hansen BS, Johansen NL, et al. Ipamorelin, the first selective growth hormone secretagogue. Eur J Endocrinol. 1998;139(5):552–561. doi:10.1530/eje.0.1390552

1. Johansen PB, Nowak J, Skjaerbaek C, et al. Ipamorelin, a new growth-hormone-releasing peptide, induces longitudinal bone growth in rats. Growth Horm IGF Res. 1999;9(2):106–113. doi:10.1054/ghir.1999.9998