Ipamorelin
Ipamorelin — A selective growth hormone secretagogue pentapeptide that stimulates GH release with minimal effect on cortisol, prolactin, or ACTH levels.
What Is Ipamorelin?
Ipamorelin is a synthetic pentapeptide (Aib-His-D-2-Nal-D-Phe-Lys-NH₂) that acts as a selective growth hormone secretagogue. With a molecular weight of 711.85 Da, it was developed by Novo Nordisk in the 1990s as part of a program to create GH-releasing compounds with minimal side effects.
What distinguishes ipamorelin from earlier secretagogues like GHRP-6 is its high selectivity. It stimulates growth hormone release without significantly affecting cortisol, prolactin, or ACTH levels at effective doses, making it one of the cleanest GH secretagogues studied.
Mechanism of Action
Ipamorelin binds to the ghrelin receptor (GHS-R1a) on pituitary somatotroph cells, triggering an intracellular calcium signaling cascade that results in growth hormone vesicle exocytosis. Unlike ghrelin, ipamorelin does not stimulate appetite through hypothalamic pathways at research doses.
The GH release follows a pulsatile pattern that mimics natural physiology, which is considered advantageous compared to continuous GH administration. Peak GH levels occur approximately 30-40 minutes after administration in animal models, with return to baseline within 2-3 hours.
Research Profile
- GH secretion: Dose-dependent, selective GH release confirmed in rat and swine models without cortisol or prolactin elevation (Raun et al., European Journal of Endocrinology, 1998)
- Bone density: Studies in ovariectomized rat models showed increased bone mineral content and bone formation markers
- Body composition: Animal studies demonstrated reduction in fat mass with preservation of lean tissue over extended administration periods
- Synergy with GHRH analogs: Co-administration with CJC-1295 has shown amplified GH release compared to either compound alone
Storage and Reconstitution
Store lyophilized ipamorelin at -20°C. Reconstitute with bacteriostatic water at a typical concentration of 2-5 mg/mL. The reconstituted solution should be clear and colorless. Any cloudiness or particulate matter indicates degradation. Use reconstituted solution within 28 days when stored at 2-8°C.
Frequently Asked Questions
What is Ipamorelin?
A selective growth hormone secretagogue pentapeptide that stimulates GH release with minimal effect on cortisol, prolactin, or ACTH levels.
Why is Ipamorelin important in peptide research?
Ipamorelin is a fundamental concept in compound as it relates to peptide science. It directly influences experimental design, compound characterization, and the reliability of research outcomes across biochemistry and molecular biology disciplines.