Description
GHRP-2 Peptide
GHRP-2 is a synthetic peptide analogous to the endogenous peptide ghrelin (1). Ghrelin is naturally occurring, first isolated from the stomach, composed of 28 amino acids, and helps regulate food intake, growth hormone release, and wound recovery (11). Growth hormone-releasing peptide GHRP 2 may induce the secretion of growth hormones (HGH) and may help maintain the required HGH concentrations.
Bovine studies have suggested that GHRP-2 peptide exhibits potential in the following areas (4):
- Possibly acting on pituitary cells, stimulating secretion of GH
- May bind with growth hormone release factor (GRF) receptor
- Possibly acts on calcium channels, inducing secretion of calcium and GH release due to calcium influx
- May stimulate cAMP pathway and protein kinase C
GHRP-2 has been researched for its potential binding activity, and may possibly stimulate adenyl cyclase activity. This may result in cAMP production and activation of protein kinase. Both elevated levels of cAMP and protein kinase may lead to increased calcium influx and subsequent growth hormone secretion (5).
Research and Clinical studies
GHRP-2 Peptide and GH Activity
This clinical study (7) was conducted to understand the action of two synthetic GHRPs: GHRP-2 and Hexarelin (HEX) on growth hormones, prolactin, adrenocorticotropic hormone (ACTH) and cortisol concentrations. Two subject groups were studied – one, with six subjects aged between 22 and 27 years and the second, with six subjects aged between 66 and 73 years. Both groups were presented in positively correlated concentrations of both peptides. Researchers suggested there was a positive correlation between concentration and GH release in the subjects.
GHRP-2 Peptide and Appetite
In this clinical study (2), seven male subjects were divided into two groups, one of which was presented with GHRP-2 and the other with saline. They were then taken to a buffet meal to measure their food intake. It was reported by the researchers that the GHRP-2 subjects ate an average of 36% more than the saline subjects, with every subject reportedly exhibiting increased food intake when measured against their respective bodyweight. Furthermore, the GH levels also presented significant incremental increases in GHRP-2 subjects as compared to saline subjects.
GHRP-2 Peptide and GH Deficiency
The most common diagnostic tool for GH deficiency is the insulin tolerance test (ITT), which may cause contraindications. A clinical study (8) aimed to explore the potential of GHRP-2 as a diagnostic resource for GH deficiency. The study reported 135 subjects who were first tested via ITT. Of these subjects, the study indicated 77 exhibited normal insulin tolerance and 58 exhibited GH peak levels of less than three. Post overnight fasting, all subjects were presented GHRP-2. After 2 hours, their blood samples were collected and tested. Upon analysis, it was reported by the researchers that the GH levels peaked after one hour of GHRP-2 in all subjects. These results were reportedly reproducible upon repetition of the tests.
An additional clinical study (9) was conducted to research the diagnostic properties of GHRP-2 on young subjects with GH deficiency (GHD) in comparison to the conventional compounds. 24 subjects with GHD were enrolled in this study. All subjects were presented with at least one conventional compound and later presented with GHRH and GHRP-2. All subjects were first given GHRP-2. When measured, the serum GH levels appeared significantly increased in these subjects. 21 subjects who demonstrated a robust response to the peptide were then presented with GHRP-2 and GHRH in combination. All subjects exhibited an apparent positive response in their GH levels, according to the researchers.
Combination Studies with TRH and GnRH
This clinical study (10) was conducted on subjects with prolonged hypo-somatotropism, hypogonadism, or hypothyroid complications to evaluate the action of compounds of GHRP-2, Thyrotropin releasing hormone (TRH), and Gonadotropin releasing hormone (GnRH) with GHRP-2 alone and with GHRP-2 and TRH in combination. 33 male subjects were enrolled in the study. Over 5 days, 7 subjects were presented with a placebo, 9 subjects with GHRP-2 every hour, 9 subjects with GHRP-2 + TRH every hour, and the remainder subjects with GHRP-2 + TRH + GnRH every 90 minutes. Serum samples were collected on the first and last night of the study. After the results were analyzed, researchers suggested that the combination of GHRP-2 + GnRH + TRH induced the greatest apparent activation of growth hormones along thyroid stimulating hormone and luteinizing hormone axes, along with other possible metabolic effects. These actions were reported to be absent with GHRP-2 solo presentation and only partially seen with GHRP-2 and TRH combination.
GHRP-2 peptide is available for research and laboratory purposes only. Please review and adhere to our Terms and Conditions before ordering.
References:
1. Garcia JM, Merriam GR, Kargi AY. Growth Hormone in Aging. [Updated 2019 Oct 7]. In: Feingold KR, Anawalt B, Boyce A, et al., editors. Endotext [Internet]. South Dartmouth (MA): MDText.com https://www.ncbi.nlm.nih.gov/books/NBK279163/
2. Laferrère, Blandine et al. “Growth hormone releasing peptide-2 (GHRP-2), like ghrelin, increases food intake in healthy men.” The Journal of clinical endocrinology and metabolism vol. 90,2 (2005): 611-4. https://www.ncbi.nlm.nih.gov/pmc/articles/PMC2824650/
3. Bowers CY. History to the discovery of ghrelin. Methods Enzymol. 2012;514:3-32. doi: 10.1016/B978-0-12-381272-8.00001-5. PMID: 22975043. https://pubmed.ncbi.nlm.nih.gov/22975043/
4. Roh SG, He ML, Matsunaga N, Hidaka S, Hidari H. Mechanisms of action of growth hormone-releasing peptide-2 in bovine pituitary cells. J Anim Sci. 1997 Oct;75(10):2744-8. doi: 10.2527/1997.75102744x. PMID: 9331879. https://pubmed.ncbi.nlm.nih.gov/9331879/
5. Asad Rahim, Stephen M. Shalet, in Growth Hormone Secretagogues, 1999. Does desensitization to growth hormone secretagogues occur? https://www.sciencedirect.com/topics/medicine-and-dentistry/pralmorelin
6. Furuta S, Shimada O, Doi N, Ukai K, Nakagawa T, Watanabe J, Imaizumi M. General pharmacology of KP-102 (GHRP-2), a potent growth hormone-releasing peptide. Arzneimittelforschung. 2004;54(12):868-80. doi: 10.1055/s-0031-1297042. PMID: 15646371. https://pubmed.ncbi.nlm.nih.gov/15646371/
7. Emanuela Arvat, Lidia Di Vito, Barbara Maccagno, Fabio Broglio, Muni F Boghen, Romano Deghenghi, Franco Camanni, Ezio Ghigo, Effects of GHRP-2 and Hexarelin, Two Synthetic GH-Releasing Peptides, on GH, Prolactin, ACTH and Cortisol Levels in Man. Comparison with the Effects of GHRH, TRH and hCRH, Peptides, Volume 18, Issue 6, 1997, Pages 885-891, ISSN 0196-9781, https://doi.org/10.1016/S0196-9781(97)00016-8
8. Chihara K, Shimatsu A, Hizuka N, Tanaka T, Seino Y, Katofor Y; KP-102 Study Group. A simple diagnostic test using GH-releasing peptide-2 in adult GH deficiency. Eur J Endocrinol. 2007 Jul;157(1):19-27. doi: 10.1530/EJE-07-0066. https://pubmed.ncbi.nlm.nih.gov/17609397/
9. Pihoker C, Middleton R, Reynolds GA, Bowers CY, Badger TM. Diagnostic studies with intravenous and intranasal growth hormone-releasing peptide-2 in children of short stature. J Clin Endocrinol Metab. 1995 Oct;80(10):2987-92. https://pubmed.ncbi.nlm.nih.gov/7559885/
10. Van den Berghe G, Baxter RC, Weekers F, Wouters P, Bowers CY, Iranmanesh A, Veldhuis JD, Bouillon R. The combined administration of GH-releasing peptide-2 (GHRP-2), TRH and GnRH to men with prolonged critical illness evokes superior endocrine and metabolic effects compared to treatment with GHRP-2 alone. Clin Endocrinol (Oxf). 2002 May;56(5):655-69. https://pubmed.ncbi.nlm.nih.gov/12030918/
11. GHRP 2, GPA 748, Growth Hormone-Releasing Peptide 2, KP-102 D, KP-102 LN, KP-102D, KP-102 LN. https://link.springer.com/article/10.2165/00126839-200405040-00011#
12. Phung LT, Sasaki A, Lee HG, Vega RA, Matsunaga N, Hidaka S, Kuwayama H, Hidari H. Effects of the administration of growth hormone-releasing peptide-2 (GHRP-2) orally by gavage and in feed on growth hormone release in swine. Domest Anim Endocrinol. 2001 Jan;20(1):9-19. https://pubmed.ncbi.nlm.nih.gov/11164330/
13. 2021 WADA Prohibited list. https://www.wada-ama.org/en/
NOTE: These products are intended for laboratory research use only. GHRP 2 for sale is not intended for personal use. Please review and adhere to our Terms and Conditions before ordering.
Dr. Marinov (MD, Ph.D.) is a researcher and chief assistant professor in Preventative Medicine & Public Health. Prior to his professorship, Dr. Marinov practiced preventative, evidence-based medicine with an emphasis on Nutrition and Dietetics. He is widely published in international peer-reviewed scientific journals and specializes in peptide therapy research.
