Ipamorelin Increases Bone Growth Rate in a Dose-Dependent Manner in Rats
Daily ipamorelin injections increased longitudinal bone growth rate, body weight, and GH release dose-dependently in rats over 15 days, without desensitization of the GH response.
Quick Facts
What This Study Found
Ipamorelin (18-450 μg/day SC, three daily injections for 15 days) increased longitudinal bone growth rate and body weight dose-dependently in rats, with sustained GH release throughout the treatment period.
Key Numbers
How They Did This
Animal study in rats. Ipamorelin at 0, 18, 90, and 450 μg/day was injected subcutaneously three times daily for 15 days. Longitudinal bone growth rate (proximal tibial epiphysis), body weight, and plasma GH were measured.
Why This Research Matters
This is the first demonstration that ipamorelin can translate its selective GH-releasing activity into actual bone growth. The sustained response without desensitization is particularly important for potential therapeutic applications.
The Bigger Picture
Growth hormone deficiency causes short stature in children and bone loss in adults. A selective GH secretagogue that sustainably promotes bone growth could offer an alternative to GH injections with fewer side effects.
What This Study Doesn't Tell Us
Rat study with relatively short duration. Bone growth rate in young growing rats may not predict effects in adult bone metabolism. No comparison to direct GH injection.
Questions This Raises
- ?Does ipamorelin maintain bone growth effects over longer treatment periods?
- ?Could ipamorelin treat growth hormone deficiency-related short stature in children?
- ?Does the bone growth effect translate to increased bone density in adults?
Trust & Context
- Key Stat:
- No desensitization Ipamorelin maintained its GH-releasing effect throughout 15 days of three-daily dosing, with dose-dependent bone growth
- Evidence Grade:
- Preliminary animal evidence with clear dose-response in bone growth and body weight, with the advantage of sustained GH response over the treatment period.
- Study Age:
- Published in 1999. Ipamorelin's bone and growth effects have been further studied, contributing to its profile as a potentially therapeutic GH secretagogue.
- Original Title:
- Ipamorelin, a new growth-hormone-releasing peptide, induces longitudinal bone growth in rats.
- Published In:
- Growth hormone & IGF research : official journal of the Growth Hormone Research Society and the International IGF Research Society, 9(2), 106-13 (1999)
- Authors:
- Johansen, P B(4), Nowak, J(2), Skjaerbaek, C, Flyvbjerg, A, Andreassen, T T, Wilken, M, Orskov, H
- Database ID:
- RPEP-00530
Evidence Hierarchy
Tests effects in animals (usually mice or rats), not humans.
What do these levels mean? →Frequently Asked Questions
Can ipamorelin make bones grow?
In this rat study, yes — ipamorelin increased the rate of bone growth in a dose-dependent manner. This shows its GH-releasing effect translates into actual tissue effects, not just blood hormone levels.
Why is the lack of desensitization important?
Many hormonal drugs lose effectiveness over time as the body adapts. Ipamorelin maintained its GH-stimulating effect throughout the study, suggesting it could work for long-term therapeutic use without requiring dose increases.
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Cite This Study
https://rethinkpeptides.com/research/RPEP-00530APA
Johansen, P B; Nowak, J; Skjaerbaek, C; Flyvbjerg, A; Andreassen, T T; Wilken, M; Orskov, H. (1999). Ipamorelin, a new growth-hormone-releasing peptide, induces longitudinal bone growth in rats.. Growth hormone & IGF research : official journal of the Growth Hormone Research Society and the International IGF Research Society, 9(2), 106-13.
MLA
Johansen, P B, et al. "Ipamorelin, a new growth-hormone-releasing peptide, induces longitudinal bone growth in rats.." Growth hormone & IGF research : official journal of the Growth Hormone Research Society and the International IGF Research Society, 1999.
RethinkPeptides
RethinkPeptides Research Database. "Ipamorelin, a new growth-hormone-releasing peptide, induces ..." RPEP-00530. Retrieved from https://rethinkpeptides.com/research/johansen-1999-ipamorelin-a-new-growthhormonereleasing
Access the Original Study
Study data sourced from PubMed, a service of the U.S. National Library of Medicine, National Institutes of Health.
This study breakdown was produced by the RethinkPeptides research team. We analyze and report published research findings without making health recommendations. All interpretations are based solely on the published abstract and study data.